patch 8.2.3970: error messages are spread out

Problem:    Error messages are spread out.
Solution:   Move more errors to errors.h.
diff --git a/src/evalvars.c b/src/evalvars.c
index ea98861..a54158f 100644
--- a/src/evalvars.c
+++ b/src/evalvars.c
@@ -622,7 +622,7 @@
 	p = skiptowhite(marker);
 	if (*skipwhite(p) != NUL && *skipwhite(p) != comment_char)
 	{
-	    semsg(_(e_trailing_arg), p);
+	    semsg(_(e_trailing_characters_str), p);
 	    return NULL;
 	}
 	*p = NUL;
@@ -802,7 +802,7 @@
 	    if (vim9script)
 	    {
 		if (!ends_excmd2(eap->cmd, skipwhite(argend)))
-		    semsg(_(e_trailing_arg), argend);
+		    semsg(_(e_trailing_characters_str), argend);
 		else
 		    // Vim9 declaration ":var name: type"
 		    arg = vim9_declare_scriptvar(eap, arg);
@@ -1206,7 +1206,7 @@
 	    {
 		emsg_severe = TRUE;
 		if (!did_emsg)
-		    semsg(_(e_trailing_arg), arg);
+		    semsg(_(e_trailing_characters_str), arg);
 		break;
 	    }
 	}
@@ -1691,7 +1691,7 @@
 		if (name_end != NULL)
 		{
 		    emsg_severe = TRUE;
-		    semsg(_(e_trailing_arg), name_end);
+		    semsg(_(e_trailing_characters_str), name_end);
 		}
 		if (!(eap->skip || error))
 		    clear_lval(&lv);
@@ -4044,7 +4044,7 @@
 	clear_lval(redir_lval);
 	if (redir_endp != NULL && *redir_endp != NUL)
 	    // Trailing characters are present after the variable name
-	    semsg(_(e_trailing_arg), redir_endp);
+	    semsg(_(e_trailing_characters_str), redir_endp);
 	else
 	    semsg(_(e_invalid_argument_str), name);
 	redir_endp = NULL;  // don't store a value, only cleanup