re PR target/15266 (libgfortran doesn't compile on IRIX 5.3)

	PR libfortran/15266
	* inclhack.def (broken_cabs): Mention IRIX 5/6 problem.
	Use double quotes in select so \t matches tabs.
	Add IRIX testcase.
	* fixincl.x: Regenerate.
	* tests/base/math.h [BROKEN_CABS_CHECK]: Adapt for new testcase.

From-SVN: r100960