drm/amdgpu: rename fiji_smumgr.h to fiji_smum.h

This conflicts with fiji_smumgr.h from powerplay
in DKMS environment

Signed-off-by: Jammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Jordan Lazare <Jordan.Lazare@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/fiji_dpm.c b/drivers/gpu/drm/amd/amdgpu/fiji_dpm.c
index 8f9845d..4b0e45a 100644
--- a/drivers/gpu/drm/amd/amdgpu/fiji_dpm.c
+++ b/drivers/gpu/drm/amd/amdgpu/fiji_dpm.c
@@ -24,7 +24,7 @@
 #include <linux/firmware.h>
 #include "drmP.h"
 #include "amdgpu.h"
-#include "fiji_smumgr.h"
+#include "fiji_smum.h"
 
 MODULE_FIRMWARE("amdgpu/fiji_smc.bin");