clearxlogtail - clearxlogtail: Replace <err.h> and err() with portable

Log Message:
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Replace <err.h> and err() with portable code.

Modified Files:
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clearxlogtail:
pg_clearxlogtail.c (r1.1 -> r1.2)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/clearxlogtail/clearxlogtail/pg_clearxlogtail.c.diff?r1=1.1&amp;r2=1.2)