fs/cifs: Assign boolean values to a bool variable

Fix the following coccicheck warnings:

./fs/cifs/connect.c:3386:2-21: WARNING: Assignment of 0/1 to
bool variable.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Zhong <abaci-bugfix@linux.alibaba.com>
Signed-off-by: Steve French <stfrench@microsoft.com>