say.c: correct time for polish

In ast_say_date_with_format_pl(), change ast_say_number() to
use tm_sec instead of tm_mn.

(closes issue ASTERISK-22856)
Reported by: Robert Mordec
Review: https://reviewboard.asterisk.org/r/3082/
Patches:
     say.c.patch uploaded by veilen (license 6555)
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Merged revisions 404456 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 404457 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 404458 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@404461 65c4cc65-6c06-0410-ace0-fbb531ad65f3