drm/amdgpu: Clean up errors in navi12_ip_offset.h

Fix the following errors reported by checkpatch:

ERROR: open brace '{' following struct go on the same line
Signed-off-by: chenxuebing <chenxb_99091@126.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/include/navi12_ip_offset.h

@@ -25,13 +25,11 @@
 #define MAX_SEGMENT                                        5
 
 
-struct IP_BASE_INSTANCE
-{
+struct IP_BASE_INSTANCE {
     unsigned int segment[MAX_SEGMENT];
 };
 
-struct IP_BASE
-{
+struct IP_BASE {
     struct IP_BASE_INSTANCE instance[MAX_INSTANCE];
 } __maybe_unused;