patch 8.2.2372: confusing error message for wrong :let command

Problem:    Confusing error message for wrong :let command.
Solution:   Only check for type in Vim9 script.

src/evalvars.c

@@ -1062,6 +1062,7 @@ skip_var_list(
 skip_var_one(char_u *arg, int include_type)
 {
     char_u	*end;
+    int		vim9 = in_vim9script();
 
     if (*arg == '@' && arg[1] != NUL)
 	return arg + 2;
@@ -1070,10 +1071,10 @@ skip_var_one(char_u *arg, int include_type)
 
     // "a: type" is declaring variable "a" with a type, not "a:".
     // Same for "s: type".
-    if (end == arg + 2 && end[-1] == ':')
+    if (vim9 && end == arg + 2 && end[-1] == ':')
 	--end;
 
-    if (include_type && in_vim9script())
+    if (include_type && vim9)
     {
 	if (*end == ':')
 	    end = skip_type(skipwhite(end + 1), FALSE);

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2372,
 /**/
     2371,
 /**/