Revert "Fix WHOIS reply not respecting a lack of the multi-prefix cap…

…ability"

A server handling a remote WHOIS cannot safely use IsCapable() to determine
if the client has multi-prefix enabled or not.

This is because client capabilities are not shared between servers; and the
IsCapable() macro dereferences source_p->localClient which will be NULL if
source_p is not on this server.

Instead rework the commit to always pretend that multi-prefix is not
enabled, to still respect the fact that multiple prefixes should not be
returned in case a client does not have multi-prefix enabled.

This reverts commit 4633665

modules/m_whois.c

@@ -279,7 +279,7 @@ single_whois(struct Client *source_p, struct Client *target_p, int operspy)
 			{
 				send_multiline_item(source_p, "%s%s%s",
 						hdata_vis.approved ? "" : "!",
-						find_channel_status(mt, IsCapable(source_p, CLICAP_MULTI_PREFIX)),
+						find_channel_status(mt, 0),
 						chptr->chname);
 			}
 		}