Remove unused libxml headers. (#3490)

Fixes fa76d52 ("Remove obsolete libxml dependency").

This fixes building on NixOS with failures like `../src/nemo-main.c:42:10: fatal error: libxml/parser.h: No such file or directory`.

Author: bobby285271

libnemo-private/nemo-directory-async.c

@@ -34,7 +34,6 @@
 #include "nemo-link.h"
 #include <eel/eel-glib-extensions.h>
 #include <gtk/gtk.h>
-#include <libxml/parser.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <libxapp/xapp-favorites.h>

libnemo-private/nemo-directory-private.h

@@ -29,7 +29,6 @@
 #include <libnemo-private/nemo-file.h>
 #include <libnemo-private/nemo-monitor.h>
 #include <libnemo-extension/nemo-info-provider.h>
-#include <libxml/tree.h>
 
 typedef struct LinkInfoReadState LinkInfoReadState;
 typedef struct FileMonitors FileMonitors;

libnemo-private/nemo-file.c

@@ -63,7 +63,6 @@
 #include <libnemo-extension/nemo-file-info.h>
 #include <libnemo-extension/nemo-extension-private.h>
 #include <libxapp/xapp-favorites.h>
-#include <libxml/parser.h>
 #include <pwd.h>
 #include <stdlib.h>
 #include <sys/time.h>

src/nemo-desktop-main.c

@@ -39,8 +39,6 @@
 #include <gtk/gtk.h>
 #include <gio/gdesktopappinfo.h>
 
-#include <libxml/parser.h>
-
 #ifdef HAVE_LOCALE_H
 #include <locale.h>
 #endif

src/nemo-main.c

@@ -39,8 +39,6 @@
 #include <gtk/gtk.h>
 #include <gio/gdesktopappinfo.h>
 
-#include <libxml/parser.h>
-
 #ifdef HAVE_LOCALE_H
 #include <locale.h>
 #endif