modem-utilities: Update OWNERS file.

BUG=None
TEST=None

Change-Id: I2eb36f23ebd7681ea53d7bd9a0922f30f6b6c8a0
Reviewed-on: https://chromium-review.googlesource.com/191922
Reviewed-by: Prathmesh Prabhu <pprabhu@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
1 file changed