samba4: bump to version 4.1.13

Also add hash file.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/samba4/samba4.hash

@@ -0,0 +1,2 @@
+# Locally calculated after checking pgp signature
+sha256	737907f4ed3a71f6ec12638387aff7cda4764f8c2eb18deeca16e2fb7ed66c9f	samba-4.1.13.tar.gz

package/samba4/samba4.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-SAMBA4_VERSION = 4.1.12
+SAMBA4_VERSION = 4.1.13
 SAMBA4_SITE = http://ftp.samba.org/pub/samba/stable
 SAMBA4_SOURCE = samba-$(SAMBA4_VERSION).tar.gz
 SAMBA4_LICENSE = GPLv3+