Fix documentation of xmpp_tlscert_get_dnsname()

`MAX_NUM_DNSNAMES` was replaced by a dynamically sized array, but the
documentation hasn't been updated.

Fixes: f23ac83 ("add callback functionality on certificate verification failure")
Signed-off-by: Steffen Jaeckel <s@jaeckel.eu>

src/tls.c

@@ -109,8 +109,6 @@ const char *xmpp_tlscert_get_pem(const xmpp_tlscert_t *cert)
 }
 
 /** Get the dnsName entries out of the SubjectAlternativeNames.
- *
- *  Note: Max. `MAX_NUM_DNSNAMES` are supported.
  *
  *  @param cert a Strophe TLS certificate object
  *  @param n which dnsName entry