analyzer: show close event for use_after_close diagnostic

analyzer: show close event for use_after_close diagnostic

This patch saves the "close" event in use_after_close diagnostic
and shows it where possible.

gcc/analyzer/ChangeLog:
	* sm-fd.cc (use_after_close): save the "close" event and
	show it where possible.

gcc/testsuite/ChangeLog:
	* gcc.dg/analyzer/fd-4.c (test_3): change the message note to conform to the
	changes in analyzer/sm-fd.cc
	(test_4): Likewise.

Signed-off-by: Immad Mir <mirimmad@outlook.com>