arm_adi_v5: split ROM table loop from generic coresight

arm_adi_v5: split ROM table loop from generic coresight

During ROM table parsing, each ROM table entry points to a
CoreSight component that can, in turn, be another ROM table.

Split the specific code for ROM table handling from the generic
CoreSight code.
Log an error if a ROM table entry cannot be read.

Change-Id: I5ad106a99b9c21ddb48b5b162ae87101e4f49878
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/6816
Tested-by: jenkins