extract_utils: Drop string after semicolon when parsing destination

This fixes parsing when arguments contain colons, a typical usecase
would be:
-vendor/app/TimeService/TimeService.apk;:timeservice_app_cert

Change-Id: I7500ae09632632ddc10734d9b1df267e28286b67
diff --git a/build/tools/extract_utils.sh b/build/tools/extract_utils.sh
index 98145bb..6d0fb12 100644
--- a/build/tools/extract_utils.sh
+++ b/build/tools/extract_utils.sh
@@ -130,7 +130,7 @@
 # output: "dst" if present, "src" otherwise.
 #
 function target_file() {
-    local SPEC="$1"
+    local SPEC="${1%%;*}"
     local SPLIT=(${SPEC//:/ })
     local ARGS="$(target_args ${SPEC})"
     local DST=