patch 8.2.4531: LGTM warnings for condition and buffer size

Problem:    LGTM warnings for condition always true and buffer size too small.
Solution:   Remove the useless condition.  Make the buffer larger. (Goc
            Dundar, closes #9914)

src/term.c

@@ -6370,7 +6370,7 @@ req_codes_from_term(void)
     static void
 req_more_codes_from_term(void)
 {
-    char	buf[11];
+    char	buf[23];  // extra size to shut up LGTM
     int		old_idx = xt_index_out;
 
     // Don't do anything when going to exit.