smb3: do not attempt multichannel to server which does not support it

smb3: do not attempt multichannel to server which does not support it

commit 9c2dc11df50d1c8537075ff6b98472198e24438e upstream.

We were ignoring CAP_MULTI_CHANNEL in the server response - if the
server doesn't support multichannel we should not be attempting it.

See MS-SMB2 section 3.2.5.2

Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-By: Tom Talpey <tom@talpey.com>
Cc: <stable@vger.kernel.org> # v5.8+
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>