smbd: let mark_file_modified() always call trigger_write_time_update()

smbd: let mark_file_modified() always call trigger_write_time_update()

Preperatory change: the next commit will reset fsp->update_write_time_on_close
in the event handler, so this change ensures it gets set again for any
subsequent write.

This will NOT always result in a write-time update because
trigger_write_time_update() has its own only-once logic using the internal
variable fsp->update_write_time_triggered.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14320

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
(cherry picked from commit 53de2da7acfc24513082190502d93306c12b7434)