drm/radeon: Mark all possible functions / structs as static

Let's allow GCC to optimize better.

This exposed some five unused functions, but this patch doesn't remove them.

Signed-off-by: Lauri Kasanen <cand@gmx.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon_test.c b/drivers/gpu/drm/radeon/radeon_test.c
index 7c16540..587c09a 100644
--- a/drivers/gpu/drm/radeon/radeon_test.c
+++ b/drivers/gpu/drm/radeon/radeon_test.c
@@ -313,7 +313,7 @@
 		printk(KERN_WARNING "Error while testing ring sync (%d).\n", r);
 }
 
-void radeon_test_ring_sync2(struct radeon_device *rdev,
+static void radeon_test_ring_sync2(struct radeon_device *rdev,
 			    struct radeon_ring *ringA,
 			    struct radeon_ring *ringB,
 			    struct radeon_ring *ringC)