Add a unit test for scoped_ignore_sigpipe

gdb/ChangeLog:
yyyy-mm-dd  Pedro Alves  <pedro@palves.net>

	* Makefile.in (SELFTESTS_SRCS): Add
	unittests/scoped_ignore_signal-selftests.c.
	* unittests/scoped_ignore_signal-selftests.c: New.

Change-Id: Idce24aa9432a3f1eb7065bc9aa030b1d0d7dcad5
3 files changed