libvpx: Update ios generated asm offsets dependencies.

Ios's path to libvpx_asm_offsets_vp8.a was wrong.

BUG=377062
TBR=tomfinegan@chromium.org

Review URL: https://codereview.chromium.org/305703002

git-svn-id: http://src.chromium.org/svn/trunk/deps/third_party/libvpx@273250 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
1 file changed