initscripts: Add generic function to get the filesystem type of a volume

Signed-off-by: Stefan Schantl <stefan.schantl@ipfire.org>
Reviewed-by: Michael Tremer <michael.tremer@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>

src/initscripts/system/functions

@@ -883,3 +883,11 @@ running_on_oci() {
 	# We are not running on OCI
 	return 1
 }
+
+volume_fs_type() {
+	if [ ! -d "${1}" ]; then
+		return
+	fi
+
+	stat -f --format="%T" ${1}
+}