Set M4 directory
Set M4 directory

Removes a build warning

(cherry picked from commit e76eb32b5fd46bbf5f87742fee9975efa5e6a071)
From linaro: git://git.linaro.org/arm/xorg/driver/xf86-video-armsoc.git

Signed-off-by: Daniel Kurtz <31914e832df1cd8e5daa417106c0c6f5297b27d7@chromium.org>

BUG=chromium:260197
TEST=manual build and sanity check ui on device

Change-Id: Ibe114c44b3dfe84dc392d8258955d36e6cf0821b
Reviewed-on: https://chromium-review.googlesource.com/62171
Reviewed-by: Daniel Kurtz <31914e832df1cd8e5daa417106c0c6f5297b27d7@chromium.org>
Commit-Queue: Daniel Kurtz <31914e832df1cd8e5daa417106c0c6f5297b27d7@chromium.org>
Tested-by: Daniel Kurtz <31914e832df1cd8e5daa417106c0c6f5297b27d7@chromium.org>

markyzq/armsoc-rockchip,markyzq/armsoc-rockchip