patch 8.2.3562: cannot add color names

Problem:    Cannot add color names.
Solution:   Add the v:colornames dictionary. (Drew Vogel, closes #8761)
diff --git a/src/vim.h b/src/vim.h
index 0ce0e96..31d4bde 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -2044,7 +2044,8 @@
 #define VV_ARGV		96
 #define VV_COLLATE      97
 #define VV_EXITING	98
-#define VV_LEN		99	// number of v: vars
+#define VV_COLORNAMES   99
+#define VV_LEN		100	// number of v: vars
 
 // used for v_number in VAR_BOOL and VAR_SPECIAL
 #define VVAL_FALSE	0L	// VAR_BOOL