arm_adi_v5: parse ROM tables behind SoC-600 APv1 adapter

arm_adi_v5: parse ROM tables behind SoC-600 APv1 adapter

Arm "CoreSight System-on-Chip SoC-600" specification describes a
bridge "Access Port v1 adapter" aimed to "connect a legacy Access
Port (AP) ... into an CoreSight Architecture v3 system".

A ROM table can be located in the "legacy" part of the system,
on the legacy AP behind the APv1 adapter.

For the purpose of scanning the ROM tables, consider an ADIv6
SoC-600 APv1 adapter as an ADIv5 AP.

Change-Id: I97d42fb77013c1251fb68d0caa4274086bf38a70
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/6827
Tested-by: jenkins