s3:smb2: debug mentions function name fewer times

s3:smb2: debug mentions function name fewer times

There was a complaint about messages like this

../../source3/smbd/smb2_server.c:4058(smbd_smb2_request_error_ex)
smbd_smb2_request_error_ex: smbd_smb2_request_error_ex: idx[1]
status[NT_STATUS_OBJECT_NAME_NOT_FOUND] || at
../../source3/smbd/smb2_create.c:360

which weren't informing the admin know what was really
wrong. This patch doesn't help, but it does avoid
saying "smbd_smb2_request_error_ex" three times.

REF: https://lists.samba.org/archive/samba/2025-February/250967.html

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jennifer Sutton <jennifersutton@catalyst.net.nz>
Reviewed-by: Rowland Penny <rpenny@samba.org>