rtio: Cleanup the various define macros

Reworks the zephyr macros and pools to be objects in their own right. Each
pool can be statically defined with a Z_ private macro. The objects can
then be initialized with an rtio instance statically.

This cleans up a lot of code that was otherwise doing little bits of
management around allocation/freeing and reduces the scope those functions
has to the data it needs.

This should enable sharing the pools of sqe, cqe, and mem blocks among rtio
instances in a future improvement easily.

Signed-off-by: Tom Burdick <[email protected]>

Author: teburd

include/zephyr/linker/common-ram.ld

@@ -111,15 +111,13 @@
 	} GROUP_DATA_LINK_IN(RAMABLE_REGION, ROMABLE_REGION)
 #endif /* CONFIG_USB_DEVICE_BOS */
 
-
 #if defined(CONFIG_RTIO)
 	ITERABLE_SECTION_RAM(rtio, 4)
 	ITERABLE_SECTION_RAM(rtio_iodev, 4)
 	ITERABLE_SECTION_RAM(rtio_sqe_pool, 4)
 	ITERABLE_SECTION_RAM(rtio_cqe_pool, 4)
 #endif /* CONFIG_RTIO */
 
-
 #ifdef CONFIG_USERSPACE
 	_static_kernel_objects_end = .;
 #endif