media: mediatek: vcodec: mark vdec_vp9_slice_map_counts_eob_coef noinline

With KASAN enabled, clang fails to optimize the inline version of
vdec_vp9_slice_map_counts_eob_coef() properly, leading to kilobytes
of temporary values spilled to the stack:

drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_vp9_req_lat_if.c:1526:12: error: stack frame size (2160) exceeds limit (2048) in 'vdec_vp9_slice_update_prob' [-Werror,-Wframe-larger-than]

This seems to affect all versions of clang including the latest (clang-20),
but the degree of stack overhead is different per release.

Marking the function as noinline_for_stack is harmless here and avoids
the problem completely.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Sebastian Fricke <sebastian.fricke@collabora.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

Author: arndb

drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_vp9_req_lat_if.c

@@ -1188,7 +1188,8 @@ static int vdec_vp9_slice_setup_lat(struct vdec_vp9_slice_instance *instance,
 	return ret;
 }
 
-static
+/* clang stack usage explodes if this is inlined */
+static noinline_for_stack
 void vdec_vp9_slice_map_counts_eob_coef(unsigned int i, unsigned int j, unsigned int k,
 					struct vdec_vp9_slice_frame_counts *counts,
 					struct v4l2_vp9_frame_symbol_counts *counts_helper)