ksmbd: fix warning: comparison of distinct pointer types lacks a cast

smb2pdu.c: In function ‘smb2_open’:
./include/linux/minmax.h:20:28: warning: comparison of distinct
pointer types lacks a cast
   20 |  (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
      |                            ^~
./include/linux/minmax.h:26:4: note: in expansion of macro ‘__typecheck’
   26 |   (__typecheck(x, y) && __no_side_effects(x, y))
      |    ^~~~~~~~~~~
./include/linux/minmax.h:36:24: note: in expansion of macro ‘__safe_cmp’
   36 |  __builtin_choose_expr(__safe_cmp(x, y), \
      |                        ^~~~~~~~~~
./include/linux/minmax.h:45:19: note: in expansion of macro ‘__careful_cmp’
   45 | #define min(x, y) __careful_cmp(x, y, <)
      |                   ^~~~~~~~~~~~~
/home/linkinjeon/git/smbd_work/ksmbd/smb2pdu.c:3713:27: note: in
expansion of macro ‘min’
 3713 |     fp->durable_timeout = min(dh_info.timeout,

Fixes: c8efcc78 ("ksmbd: add support for durable handles v1/v2")
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>