drm/radeon: add UVD->DPM helper function (v5)

Add a helper function for counting the number of open stream handles.

v2: fix copy-pasta in comments and whitespace error
v3: make function static since it's only used in radeon_uvd.c
at the moment
v4: make non-static again for future changes
v5: make static again for new rework of dpm uvd changes

Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 83be8fd..fc8d03b 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -1441,6 +1441,7 @@
 	void			*saved_bo;
 	atomic_t		handles[RADEON_MAX_UVD_HANDLES];
 	struct drm_file		*filp[RADEON_MAX_UVD_HANDLES];
+	unsigned		img_size[RADEON_MAX_UVD_HANDLES];
 	struct delayed_work	idle_work;
 };