drm/amd: Set num IP blocks to 0 if discovery fails

drm/amd: Set num IP blocks to 0 if discovery fails

If discovery has failed for any reason (such as no support for a block)
then there is no need to unwind all the IP blocks in fini. In this
condition there can actually be failures during the unwind too.

Reset num_ip_blocks to zero during failure path and skip the unnecessary
cleanup path.

Suggested-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>