adjust copyright/license on a few files to match reality

From the author:
	I looked at the four files in question.  I did write getitimer03.c and I
	believe using the standard IBM copyright is correct.

	I ported the getresgid01.c code to run under Linux.  As I recall it was
	originally a Sequent test case for the Dynix/ptx OS.  Again I believe
	using the standard IBM copyright is correct.

	I did not work with the last two files, but they follow the same pattern
	as the getresgid01.c code.  There were originally part of the Dynix/ptx
	test cases.

Also note: the Makefile in question was rewritten by Cisco as part of
the build system overhaul, so use the standard copyright for that.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>