coresight: Remove unused stubs

These are a bit annoying to keep up to date when the function signatures
change. But if CONFIG_CORESIGHT isn't enabled, then they're not used
anyway so just delete them.

Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20240129154050.569566-9-james.clark@arm.com


Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>