drm/amd/display: Unconditionally print when DP sink power state fails

The previous 'commit ca9beb8a ("drm/amd/display: Add logging when
setting DP sink power state fails")', it is better to unconditionally
print "failed to power up sink", because we are returning
DC_ERROR_UNEXPECTED.

Fixes: ca9beb8a ("drm/amd/display: Add logging when setting DP sink power state fails")
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Cc: Fangzhi Zuo <Jerry.Zuo@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>