patch 8.1.0620: overuling CONF_ARGS from the environment no longer works

Problem:    Overuling CONF_ARGS from the environment no longer works. (Tony
            Mechelynck)
Solution:   Do not define any CONF_ARGS by default.
diff --git a/src/Makefile b/src/Makefile
index d866737..56e3ba6 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -323,10 +323,9 @@
 #CONF_ARGS3 = --with-global-runtime=/etc/vim,/usr/share/vim
 #CONF_ARGS4 = --with-local-dir=/usr/share
 #CONF_ARGS5 = --without-local-dir
-CONF_ARGS = $(CONF_ARGS1) $(CONF_ARGS2) $(CONF_ARGS3) $(CONF_ARGS4) $(CONF_ARGS5)
 
 # Use this one if you distribute a modified version of Vim.
-#CONF_ARGS = --with-modified-by="John Doe"
+#CONF_ARGS6 = --with-modified-by="John Doe"
 
 # GUI - For creating Vim with GUI (gvim) (B)
 # Uncomment this line when you don't want to get the GUI version, although you
@@ -1933,7 +1932,9 @@
 		$(CONF_OPT_FEAT) $(CONF_TERM_LIB) \
 		$(CONF_OPT_COMPBY) $(CONF_OPT_ACL) $(CONF_OPT_NETBEANS) \
 		$(CONF_OPT_CHANNEL) $(CONF_OPT_TERMINAL) \
-		$(CONF_ARGS) $(CONF_OPT_MZSCHEME) $(CONF_OPT_PLTHOME) \
+		$(CONF_ARGS1) $(CONF_ARGS2) $(CONF_ARGS3) $(CONF_ARGS4) \
+		$(CONF_ARGS5) $(CONF_ARGS6) \
+		$(CONF_OPT_MZSCHEME) $(CONF_OPT_PLTHOME) \
 		$(CONF_OPT_LUA) $(CONF_OPT_LUA_PREFIX) \
 		$(CONF_OPT_SYSMOUSE); \
 	fi
diff --git a/src/version.c b/src/version.c
index b1a28c1..333a98f 100644
--- a/src/version.c
+++ b/src/version.c
@@ -800,6 +800,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    620,
+/**/
     619,
 /**/
     618,