[ticket/11654] generate_text_for_display on mcp/mcp_warn.php

sub-task of ticket PHPBB3-11635:
find and fix all bypasses of generate_text_for_*

PHPBB3-11654
[ticket/11654] first parameter fail

sub-task of ticket PHPBB3-11635:
find and fix all bypasses of generate_text_for_*

PHPBB3-11654
[ticket/11654] Moved some code to reduce line width.

sub-task of ticket PHPBB3-11635:
find and fix all bypasses of generate_text_for_*

PHPBB3-11654
Merge pull request #1586 from brunoais/ticket/11654

[ticket/11654] generate_text_for_display on mcp/mcp_warn.php