cifs: do not reset chan_max if multichannel is not supported at mount

jira LE-4669
Rebuild_History Non-Buildable kernel-4.18.0-553.82.1.el8_10
commit-author Shyam Prasad N <sprasad@microsoft.com>
commit 6e5e64c

If the mount command has specified multichannel as a mount option,
but multichannel is found to be unsupported by the server at the time
of mount, we set chan_max to 1. Which means that the user needs to
remount the share if the server starts supporting multichannel.

This change removes this reset. What it means is that if the user
specified multichannel or max_channels during mount, and at this
time, multichannel is not supported, but the server starts supporting
it at a later point, the client will be capable of scaling out the
number of channels.

	Cc: stable@vger.kernel.org
	Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
	Signed-off-by: Steve French <stfrench@microsoft.com>
(cherry picked from commit 6e5e64c)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

Author: PlaidCat

fs/cifs/sess.c

@@ -155,7 +155,6 @@ int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
 	}
 
 	if (!(server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
-		ses->chan_max = 1;
 		spin_unlock(&ses->chan_lock);
 		cifs_server_dbg(VFS, "no multichannel support\n");
 		return 0;