CCA: Fix relative path in build_ffmpeg.sh

Bug: none
Test: ./build_ffmpeg.sh
Change-Id: Ia5005852432b21a4f92f3bbc2a4cbf44bef7c8b5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2288713
Auto-Submit: Wei Lee <wtlee@chromium.org>
Commit-Queue: Shik Chen <shik@chromium.org>
Reviewed-by: Shik Chen <shik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#786622}

chromeos/components/camera_app_ui/resources/src/js/lib/build_ffmpeg.sh

@@ -122,7 +122,7 @@ main() {
 
   # locate ffmpeg directory in chromium source tree
   local ffmpeg_dir
-  ffmpeg_dir=$(realpath ../../../../../../../../third_party/ffmpeg)
+  ffmpeg_dir=$(realpath ../../../../../../../third_party/ffmpeg)
   [[ -d "$ffmpeg_dir" ]] || die "ffmpeg not found"
 
   # copy ffmpeg/ into a temporary directory to patch and build