Missing field not being returned in ioctl CIFS_IOC_GET_MNT_INFO

The tcon_flags field was always being set to zero in the information
about the mount returned by the ioctl CIFS_IOC_GET_MNT_INFO instead
of being set to the value of the Flags field in the tree connection
structure as intended.

Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>