cifs: Rename cifs_strncpy_to_host and fix buffer size

There is a possibility for the path_name and node_name buffers to
overflow if they contain charcters that are >2 bytes in the local
charset. Resize the buffer allocation so to avoid this possibility.

Also, as pointed out by Jeff Layton, it would be appropriate to
rename the function to cifs_strlcpy_to_host to reflect the fact
that the copied string is always NULL terminated.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>