agl-persistent-storage-api: set BINDGEN_EXTRA_CLANG_ARGS

agl-persistent-storage-api: set BINDGEN_EXTRA_CLANG_ARGS

The agl-persistent-storage-api build was failing on hosts where the
native headers happened to not work with the clang invocation being
done during binding generation for the rocksdb wrapper crate.
To avoid this, set BINDGEN_EXTRA_CLANG_ARGS to pass in the required
cross-compile environment arguments.

Bug-AGL: SPEC-5264

Change-Id: I54af5846045285b4ccd7af5cc0087193eae79be0
Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl-demo/+/30416
Tested-by: Jenkins Job builder account
Reviewed-by: Naoto YAMAGUCHI <naoto.yamaguchi@aisin.co.jp>
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>
ci-image-build: Jenkins Job builder account
ci-image-boot-test: Jenkins Job builder account
(cherry picked from commit df7db40b80da5300dbced99aef171d1e0dada5af)
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl-demo/+/30460