extract_utils: drop the "/system/" prefix from prints of blob names

* This makes the printed output closer to the proprietary-files.txt syntax

Change-Id: I81b844bb6bb1d1a2f91a39151a892fbfc0bed20b
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
diff --git a/build/tools/extract_utils.sh b/build/tools/extract_utils.sh
index 4c76b44..4a3ab97 100644
--- a/build/tools/extract_utils.sh
+++ b/build/tools/extract_utils.sh
@@ -1013,11 +1013,7 @@
             DST_FILE="/system/${SPEC_DST_FILE}"
         fi
 
-        if [ "$SRC" = "adb" ]; then
-            printf '  - %s .. \n' "${DST_FILE}"
-        else
-            printf '  - %s \n' "${DST_FILE}"
-        fi
+        printf '  - %s \n' "${DST_FILE#/system/}"
 
         # Strip the file path in the vendor repo of "system", if present
         local VENDOR_REPO_FILE="$OUTPUT_DIR/${DST_FILE#/system}"