fix issue with extra_net_fs_list

The extra_net_fs_list variable was not being included as it should have
been for the net file systems because it was being expanded before it
was set by the user.

X-Gentoo-Bug: 374133
X-Gentoo-Bug-URL: https://bugs.gentoo.org/show_bug.cgi?id=374133

sh/rc-functions.sh.in

@@ -39,7 +39,7 @@ stop_addon()
 }
 
 net_fs_list="afs cifs coda davfs fuse fuse.sshfs gfs glusterfs lustre
-ncpfs nfs nfs4 ocfs2 shfs smbfs $extra_net_fs_list"
+ncpfs nfs nfs4 ocfs2 shfs smbfs"
 is_net_fs()
 {
 	[ -z "$1" ] && return 1