Add ONLY_MAN_DOCS variable to only install the man page, not the html
and ps documentation.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70589 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/Makefile b/docs/Makefile
index 47db7eb..9b706c7 100644
--- a/docs/Makefile
+++ b/docs/Makefile
@@ -33,7 +33,10 @@
 
 .PHONY: install-html install-doxygen doxygen generated
 
-install_targets := install-html
+install_targets :=
+ifndef ONLY_MAN_DOCS
+install_targets += install-html
+endif
 ifeq ($(ENABLE_DOXYGEN),1)
 install_targets += install-doxygen
 endif