drm/amdgpu: fix incompatible types in conditional expression

Use proper type.

Fixes: 9d4346bd

 ("drm/amdgpu: add VPE 6.1.0 support")
Signed-off-by: Lang Yu <Lang.Yu@amd.com>
Reviewed-by: Solomon Chiu <solomon.chiu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202309020608.FwP8QMht-lkp@intel.com


Signed-off-by: Alex Deucher <alexander.deucher@amd.com>