LE audio TMAP: Add role verification

[JingsaiLu]

Is your enhancement proposal related to a problem? Please describe.
want to discuss if we should add any abstraction layers for the different TMAP roles in tmap driver?

each TMAP role requires some special settings and low layer profile procedures.

but there is no more implementation for these in tmap.c
https://github.com/zephyrproject-rtos/zephyr/blob/main/subsys/bluetooth/audio/tmap.c

we do these in demo apps:
b926b29#diff-cc104b7b2a9cb82bee5f3b6d56b8f3a54b4d2660731f7546c26bbd2eca310f5f
f4f0f00#diff-48dd3e98c744416052457825e6733baa10cfc8d0bfa0644aee65dddab49317c4

Describe the solution you'd like
add more apis to simplify the TMAP role usages.

[Thalley]

Indeed. bt_tmap_register and bt_tmap_set_role should return an error if the supplied role is not supported by the device