gn2bp: Fix use of soong_zip with OUT_DIR=/abs/path am: dfb67ba455

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2401046

Change-Id: Ie7b0324ee12005cbce84bcee176a94218c3e65b4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>