Update nmbd profile and abstractions/samba

nmbd needs some additional permissions:
- k for /var/cache/samba/lck/* (via abstractions/samba)
- rw for /var/cache/samba/msg/ (the log only mentioned r, but that
  directory needs to be created first)
- w for /var/cache/samba/msg/* (the log didn't indicate any read access)

Reported by FLD on IRC, audit log on https://paste.debian.net/902010/



Acked-by: Steve Beattie <steve@nxnw.org> for trunk, 2.10 and 2.9

profiles/apparmor.d/abstractions/samba

@@ -14,7 +14,7 @@
   /usr/share/samba/*.dat r,
   /usr/share/samba/codepages/{lowcase,upcase,valid}.dat r,
   /var/cache/samba/ w,
-  /var/cache/samba/lck/* rw,
+  /var/cache/samba/lck/* rwk,
   /var/lib/samba/** rwk,
   /var/log/samba/cores/ rw,
   /var/log/samba/cores/** rw,

profiles/apparmor.d/usr.sbin.nmbd

@@ -20,6 +20,8 @@
   /var/{cache,lib}/samba/smb_tmp_krb5.* rw,
   /var/{cache,lib}/samba/sync.* rw,
   /var/{cache,lib}/samba/unexpected rw,
+  /var/cache/samba/msg/ rw,
+  /var/cache/samba/msg/* w,
 
   /{,var/}run/samba/** rwk,