feat(hal): Add preliminary support for LEDC

[lihanrui2913]

No description provided.

[luojia65]

Please add Signed-off-by for each of your comments.

[luojia65]

Suggested change

	/// LEDC MSB control bits.
	#[inline]
	pub const fn is_red_msb(self) -> bool {
	(self.0 & Self::LED_MSB_R) != 0
	}
	#[inline]
	pub const fn is_blue_msb(self) -> bool {
	(self.0 & Self::LED_MSB_B) != 0
	}
	#[inline]
	pub const fn is_green_msb(self) -> bool {
	(self.0 & Self::LED_MSB_G) != 0
	}
	/// Get the red LEDC MSB control bit.
	#[inline]
	pub const fn is_red_msb(self) -> bool {
	(self.0 & Self::LED_MSB_R) != 0
	}
	/// Get the blue LEDC MSB control bit.
	#[inline]
	pub const fn is_blue_msb(self) -> bool {
	(self.0 & Self::LED_MSB_B) != 0
	}
	/// Get the green LEDC MSB control bit.
	#[inline]
	pub const fn is_green_msb(self) -> bool {
	(self.0 & Self::LED_MSB_G) != 0
	}

Documentation comments are for each function, we can't write only one documentation comment for a list of functions. Use cargo doc and you will find out that the following functions other than the first one does not have a proper documentation comment,

[luojia65]

Suggested change

	use volatile_register::RW;
	//! LEDC peripheral registers.
	use volatile_register::RW;

Add module level documentations.

[lihanrui2913]

I have finished writing all the LEDC registers. Please take a look at where they need to be modified. If you think there are too many commits, I will merge them.

[luojia65]

LGTM with minor modifications applicable. Please squash your commits.

[luojia65]

For enable/disable bit, write like:

pub const fn is_wait_time0_enabled(self) -> bool
pub const fn enable_wait_time0(self) -> Self
pub const fn disable_wait_time0(self) -> Self

[luojia65]

is_dma_enabled, enable_dma, disable_dma