extract_utils: Redirect vdexextractor log to /dev/null

Change-Id: I55028997c0396d57c024e6c42a53907f6d1510c8
diff --git a/build/tools/extract_utils.sh b/build/tools/extract_utils.sh
index 1c68169..9a43fc0 100644
--- a/build/tools/extract_utils.sh
+++ b/build/tools/extract_utils.sh
@@ -845,7 +845,7 @@
             # try to extract classes.dex from boot.vdex for frameworks jars
             # fallback to boot.oat if vdex is not available
             if get_file "$JARVDEX" "$TMPDIR" "$SRC"; then
-                "$VDEXEXTRACTOR" -o "$TMPDIR/" -i "$TMPDIR/$(basename "$JARVDEX")"
+                "$VDEXEXTRACTOR" -o "$TMPDIR/" -i "$TMPDIR/$(basename "$JARVDEX")" > /dev/null
                 # Check if we have to deal with CompactDex
                 if [ -f "$TMPDIR/$(basename "${JARVDEX%.*}")_classes.cdex" ]; then
                     "$CDEXCONVERTER" "$TMPDIR/$(basename "${JARVDEX%.*}")_classes.cdex" &> /dev/null