build: fix CMP0175 warnings

The following pattern was used to add custom `make LuaJIT-foo` commands:

```cmake
add_custom_target(${PROJECT_NAME}-foo DEPENDS <...>)
add_custom_command(TARGET ${PROJECT_NAME}-foo
    COMMAND <...>
)
```

However, recent cmake versions (verified on 4.3.4) warns about the
`add_custom_command` syntax (quoted [1]):

> `add_custom_command()` rejects invalid arguments.
>
> <...>
>
> The `TARGET` form requires exactly one of `PRE_BUILD`, `PRE_LINK`, or
> `POST_BUILD` to be given. Previously, if none were given, `POST_BUILD`
> was assumed, or if multiple keywords were given, the last one was
> used.

The fix could be add the `POST_BUILD` keyword. However, it is more
natural to just use `add_custom_target` with `COMMAND` instead:

```cmake
add_custom_target(${PROJECT_NAME}-foo
    COMMAND <...>
    DEPENDS <...>
)
```

The same change is proposed to tarantool: [2].

[1]: https://cmake.org/cmake/help/latest/policy/CMP0175.html
[2]: tarantool/tarantool#13177

Reviewed-by: Sergey Kaplun <skaplun@tarantool.org>
Reviewed-by: Sergey Bronnikov <sergeyb@tarantool.org>
Signed-off-by: Sergey Kaplun <skaplun@tarantool.org>
(cherry picked from commit f3829a4)

Author: Totktonada

cmake/CodeCoverage.cmake

@@ -16,8 +16,7 @@ if(NOT GCOVR OR NOT GCOV)
 endif()
 
 file(MAKE_DIRECTORY ${COVERAGE_DIR})
-add_custom_target(${PROJECT_NAME}-coverage)
-add_custom_command(TARGET ${PROJECT_NAME}-coverage
+add_custom_target(${PROJECT_NAME}-coverage
   COMMENT "Building coverage report"
   COMMAND
     ${GCOVR}

cmake/CodeSpell.cmake

@@ -35,9 +35,8 @@ set(CODESPELL_WHITELIST
 
 set(IGNORE_WORDS ${PROJECT_SOURCE_DIR}/.codespell-ignore-words.txt)
 
-add_custom_target(${PROJECT_NAME}-codespell)
 if(CODESPELL)
-  add_custom_command(TARGET ${PROJECT_NAME}-codespell
+  add_custom_target(${PROJECT_NAME}-codespell
     COMMENT "Running codespell"
     COMMAND
       ${CODESPELL}
@@ -51,7 +50,7 @@ else()
   set(STR1 "codespell is not found,")
   set(STR2 "so ${PROJECT_NAME}-codespell target is dummy")
   string(CONCAT WARN_MSG "${STR1} ${STR2}")
-  add_custom_command(TARGET ${PROJECT_NAME}-codespell
+  add_custom_target(${PROJECT_NAME}-codespell
     COMMAND ${CMAKE_COMMAND} -E cmake_echo_color --red ${WARN_MSG}
     COMMENT ${WARN_MSG}
   )

test/CMakeLists.txt

@@ -15,9 +15,6 @@ if(LUACHECK)
   set(LUACHECK_RC ${LUACHECK_SOURCE_DIR}/.luacheckrc)
   file(GLOB_RECURSE LUACHECK_DEPS ${LUACHECK_SOURCE_DIR}/*.lua)
   add_custom_target(${PROJECT_NAME}-luacheck
-    DEPENDS ${LUACHECK_RC} ${LUACHECK_DEPS}
-  )
-  add_custom_command(TARGET ${PROJECT_NAME}-luacheck
     COMMENT "Running luacheck static analysis"
     COMMAND
       ${LUACHECK} ${LUACHECK_SOURCE_DIR}
@@ -31,10 +28,10 @@ if(LUACHECK)
     # the working directory, hence luacheck should be run in the
     # project root directory.
     WORKING_DIRECTORY ${LUACHECK_SOURCE_DIR}
+    DEPENDS ${LUACHECK_RC} ${LUACHECK_DEPS}
   )
 else()
-  add_custom_target(${PROJECT_NAME}-luacheck)
-  add_custom_command(TARGET ${PROJECT_NAME}-luacheck
+  add_custom_target(${PROJECT_NAME}-luacheck
     COMMENT "`luacheck' is not found, so ${PROJECT_NAME}-luacheck target is dummy"
   )
 endif()
@@ -45,19 +42,16 @@ if(FLAKE8)
   set(FLAKE8_RC ${FLAKE8_SOURCE_DIR}/.flake8rc)
   file(GLOB_RECURSE FLAKE8_DEPS ${FLAKE8_SOURCE_DIR}/*.py)
   add_custom_target(${PROJECT_NAME}-flake8
-    DEPENDS ${FLAKE8_DEPS}
-  )
-  add_custom_command(TARGET ${PROJECT_NAME}-flake8
     COMMENT "Running flake8 static analysis"
     COMMAND
       ${FLAKE8} ${FLAKE8_DEPS}
         --config ${FLAKE8_RC}
         --jobs ${CMAKE_BUILD_PARALLEL_LEVEL}
     WORKING_DIRECTORY ${FLAKE8_SOURCE_DIR}
+    DEPENDS ${FLAKE8_DEPS}
   )
 else()
-  add_custom_target(${PROJECT_NAME}-flake8)
-  add_custom_command(TARGET ${PROJECT_NAME}-flake8
+  add_custom_target(${PROJECT_NAME}-flake8
     COMMENT "`flake8' is not found, so ${PROJECT_NAME}-flake8 target is dummy"
   )
 endif()

test/PUC-Rio-Lua-5.1-tests/libs/CMakeLists.txt

@@ -24,11 +24,11 @@ list(APPEND TESTLIBS ${LIB2COPY})
 # subdirectory "libs/P1", to be used by tests.
 # Instead of tracking empty directory with some anchor-file for
 # git, create this directory via CMake.
-add_custom_target(PUC-Rio-Lua-5.1-tests-prepare DEPENDS ${TESTLIBS})
-add_custom_command(TARGET PUC-Rio-Lua-5.1-tests-prepare
+add_custom_target(PUC-Rio-Lua-5.1-tests-prepare
   COMMENT "Create directory for PUC-Rio Lua 5.1 tests"
   COMMAND ${CMAKE_COMMAND} -E make_directory P1
   WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+  DEPENDS ${TESTLIBS}
 )
 
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