Specify working directory and OUT_DIR to ABI tools

This commit adds `--root-dir . --root-dir $OUT_DIR:out` to the commands
of ABI tools. If the user sets non-default $OUT_DIR, the tools write
"out" instead of the actual $OUT_DIR to the ABI dumps.

Test: export OUT_DIR=~/aosp_out ; \
      make libstagefright_bufferqueue_helper.vendor
Bug: 192157880
Change-Id: I4e2d1b252273106fb6a3ecfa1727d5c91ba03444