Fix cmake install prefix with cmake-3.x
diff --git a/Makefile b/Makefile
index 49f29d7..518ea5c 100644
--- a/Makefile
+++ b/Makefile
@@ -275,7 +275,7 @@
cmake --version
$(RM) -r $(BUILDIR)/cmake/build
mkdir $(BUILDIR)/cmake/build
- cd $(BUILDIR)/cmake/build ; cmake -DPREFIX:STRING=~/install_test_dir $(CMAKE_PARAMS) .. ; $(MAKE) install ; $(MAKE) uninstall
+ cd $(BUILDIR)/cmake/build ; cmake -DCMAKE_INSTALL_PREFIX:PATH=~/install_test_dir $(CMAKE_PARAMS) .. ; $(MAKE) install ; $(MAKE) uninstall
c90build: clean
gcc -v