drm/amdgpu: fix spelling in header comment

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

include/uapi/drm/amdgpu_drm.h

@@ -297,7 +297,7 @@ union drm_amdgpu_gem_wait_idle {
 struct drm_amdgpu_wait_cs_in {
 	/* Command submission handle
          * handle equals 0 means none to wait for
-         * handle equal ~0ull meanas wait for the latest sequence number
+         * handle equals ~0ull means wait for the latest sequence number
          */
 	__u64 handle;
 	/** Absolute timeout to wait */