packet-ldap: fix regression for SASL handling
commit
19b3376a24192319a008399e8c44f1655f6dcebd
("LDAP bogus malformed errors: decoding encrypted data")
introduced 2 problems:
- guint decr_len = tvb_reported_length(decr_tvb); was
always called with decr_tvb==NULL
- dissect_ldap_payload() was not called if sasl_tree is NULL,
it needs to be called even if the tree pointer are NULL
in order to have the COL_INFO setup correctly.
I guess this should also be backported to stable branches
(together with
2e6d3b571b50f6a0df31787cb95ba0f66c4fa85f
"LDAP: SASL Buffer doesn't include Length field")
https://gitlab.com/wireshark/wireshark/-/issues/17347
Signed-off-by: Stefan Metzmacher <metze@samba.org>