Use absolute path for output.

Test: manual
Bug: 137798757
Change-Id: If2e9c31e1ff523914f5f2cecf8975e1da91c03a7
diff --git a/build_kzip.bash b/build_kzip.bash
index ccd6bad..02b346d 100755
--- a/build_kzip.bash
+++ b/build_kzip.bash
@@ -19,12 +19,13 @@
 # Build extraction files for C++ and Java. Build `merge_zips` which we use later.
 build/soong/soong_ui.bash --build-mode --all-modules --dir=$PWD -k merge_zips xref_cxx xref_java
 #Build extraction file for Go files in build/soong directory.
+declare -r abspath_out=$(realpath "${out}")
 (cd build/soong;
  ../../prebuilts/build-tools/linux-x86/bin/go_extractor \
     --goroot="${PWD}/../../prebuilts/go/linux-x86" \
     --rules=vnames.go.json \
     --canonicalize_package_corpus \
-    --output "${out}/soong/all.go.kzip" \
+    --output "${abspath_out}/soong/all.go.kzip" \
     ./... )
 
 declare -r kzip_count=$(find "$out" -name '*.kzip' | wc -l)