patch 8.1.2233: cannot get the Vim command line arguments

Problem:    Cannot get the Vim command line arguments.
Solution:   Add v:argv. (Dmitri Vereshchagin, closes #1322)
diff --git a/src/vim.h b/src/vim.h
index 7b2aa5b..de5873c 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -1990,7 +1990,8 @@
 #define VV_EVENT	90
 #define VV_VERSIONLONG	91
 #define VV_ECHOSPACE	92
-#define VV_LEN		93	// number of v: vars
+#define VV_ARGV		93
+#define VV_LEN		94	// number of v: vars
 
 // used for v_number in VAR_SPECIAL
 #define VVAL_FALSE	0L