s3: smbd: Quiet log messages from usershares for an unknown share.

s3: smbd: Quiet log messages from usershares for an unknown share.

No need to log missing shares/sharenames at debug level zero.

Keep the debug level zero for all other usershare problems.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14590

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Rowland penny <rpenny@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Fri Dec  4 20:54:06 UTC 2020 on sn-devel-184

(cherry picked from commit 8a0a7359faba642baf55a8f98ff78c0d0884d0f0)