drivers/amdgpu: Use canonical form in branch predicates

Found-by: Coccinelle
Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c b/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
index 2b8ce58..4debd0d 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
@@ -604,7 +604,7 @@
 	u32 f32_cntl;
 	int i;
 
-	if (enable == false) {
+	if (!enable) {
 		sdma_v3_0_gfx_stop(adev);
 		sdma_v3_0_rlc_stop(adev);
 	}