cifs: make new inode cache when file type is different

cifs: make new inode cache when file type is different

In spite of different file type,
 if file is same name and same inode number, old inode cache is used.
This causes that you can not cd directory, can not cat SymbolicLink.
So this patch is that if file type is different, return error.

Reproducible sample :
1. create file 'a' at cifs client.
2. repeat rm and mkdir 'a' 4 times at server, then direcotry 'a' having same inode number is created.
   (Repeat 4 times, then same inode number is recycled.)
   (When server is under RHEL 6.6, 1 time is O.K.  Always same inode number is recycled.)
3. ls -li at client, then you can not cd directory, can not remove directory.

SymbolicLink has same problem.

Bug link:
https://bugzilla.kernel.org/show_bug.cgi?id=90011

Signed-off-by: Nakajima Akira <nakajima.akira@nttcom.co.jp>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Steve French <steve.french@primarydata.com>