drm/amdgpu: use kernel is_power_of_2 rather than local version

Use the kernel provided version.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Alex Deucher 2017-06-21 12:31:41 -04:00
commit 7611750784