s3:winbind: Improve logging in winbindd_getpwsid.c

Test scenario:

$ bin/wbinfo --name-to-sid ADDOMAIN/alice
S-1-5-21-4248687961-4152985382-2800071106-1107 SID_USER (1)

$ bin/wbinfo --user-sidinfo S-1-5-21-4248687961-4152985382-2800071106-1107
ADDOMAIN/alice:*:2001107:2000513::/home/ADDOMAIN/alice:/bin/false

Signed-off-by: Pavel Filipenský <pfilipen@redhat.com>
Reviewed-by: Andreas Schneider <asn@samba.org>