freedreno: remove unused forward struct declaration

Signed-off-by: Rob Clark <robdclark@chromium.org>
diff --git a/src/gallium/drivers/freedreno/freedreno_resource.h b/src/gallium/drivers/freedreno/freedreno_resource.h
index 5369fcb..5776c7e 100644
--- a/src/gallium/drivers/freedreno/freedreno_resource.h
+++ b/src/gallium/drivers/freedreno/freedreno_resource.h
@@ -59,8 +59,6 @@
 	uint32_t size0;          /* size of first layer in slice */
 };
 
-struct set;
-
 struct fd_resource {
 	struct pipe_resource base;
 	struct fd_bo *bo;