ksmbd: fix non-IPv6 build

ksmbd: fix non-IPv6 build

The newly added procfs code fails to build when CONFIG_IPv6 is disabled:

fs/smb/server/connection.c: In function 'proc_show_clients':
fs/smb/server/connection.c:47:58: error: 'struct ksmbd_conn' has no member named 'inet6_addr'; did you mean 'inet_addr'?
   47 |                         seq_printf(m, "%-20pI6c", &conn->inet6_addr);
      |                                                          ^~~~~~~~~~
      |                                                          inet_addr
make[7]: *** [scripts/Makefile.build:279: fs/smb/server/connection.o] Error 1
fs/smb/server/mgmt/user_session.c: In function 'show_proc_sessions':
fs/smb/server/mgmt/user_session.c:215:65: error: 'struct ksmbd_conn' has no member named 'inet6_addr'; did you mean 'inet_addr'?
  215 |                         seq_printf(m, " %-40pI6c", &chan->conn->inet6_addr);
      |                                                                 ^~~~~~~~~~
      |                                                                 inet_addr

Rearrange the condition to allow adding a simple preprocessor conditional.

Fixes: b38f99c1217a ("ksmbd: add procfs interface for runtime monitoring and statistics")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>