This test does not work in all environments, so add an option to disable it.
@@ -1,6 +1,7 @@
-if(UNIX AND "${CMAKE_GENERATOR}" MATCHES "Makefile")
+if(UNIX AND "${CMAKE_GENERATOR}" MATCHES "Makefile" AND
+ NOT CMake_TEST_NO_FindPackageModeMakefileTest)
# Test whether the make is GNU make, and only add the test in this case,
# since the configured makefile in this test uses $(shell ...), which