Patch to allow us to specify an alternate runtest script when running tests.

This patch should be sent upstream.

--- dejagnu-1.5.3/Makefile.in.orig 2015-08-05 13:55:23.117124070 -0700

+++ dejagnu-1.5.3/Makefile.in 2015-08-05 13:56:42.970772105 -0700

@@ -583,7 +583,7 @@

testsuite/lib/util-defs.exp \

testsuite/libdejagnu/tunit.exp

-RUNTEST = ${top_srcdir}/runtest

+RUNTEST="$${RUNTEST_SCRIPT:-${top_srcdir}/runtest}"

RUNTESTDEFAULTFLAGS = --srcdir $(srcdir)/testsuite RUNTEST=$(RUNTEST)

AM_CXXFLAGS = -I$(top_srcdir) -g

unit_SOURCES = testsuite/libdejagnu/unit.cc