i915/perf: Fix NULL deref bugs with drm_dbg() calls
When i915 perf interface is not available dereferencing it will lead to
NULL dereferences.
As returning -ENOTSUPP is pretty clear return when perf interface is not
available.
Fixes: 2fec539112e8 ("i915/perf: Replace DRM_DEBUG with driver specific drm_dbg call")
Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v6.0+
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231027172822.2753059-1-harshit.m.mogalapalli@oracle.com
[tursulin: added stable tag]
(cherry picked from commit
36f27350ff745bd228ab04d7845dfbffc177a889)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>