patch 9.0.1527: crash when using negative value for term_cols

Problem:    Crash when using negative value for term_cols.
Solution:   Check for invalid term_cols value. (Kenta Sato, closes #12362)
diff --git a/src/job.c b/src/job.c
index 4e64ca3..2a2e531 100644
--- a/src/job.c
+++ b/src/job.c
@@ -272,7 +272,8 @@
 		*lp = tv_get_number(item);
 		if (*lp < 0)
 		{
-		    semsg(_(e_invalid_value_for_argument_str_str), hi->hi_key, tv_get_string(item));
+		    semsg(_(e_invalid_value_for_argument_str_str),
+					      hi->hi_key, tv_get_string(item));
 		    return FAIL;
 		}
 	    }
@@ -444,10 +445,19 @@
 	    }
 	    else if (STRCMP(hi->hi_key, "term_cols") == 0)
 	    {
+		int error = FALSE;
+
 		if (!(supported2 & JO2_TERM_COLS))
 		    break;
 		opt->jo_set2 |= JO2_TERM_COLS;
-		opt->jo_term_cols = tv_get_number(item);
+		opt->jo_term_cols = tv_get_number_chk(item, &error);
+		if (error)
+		    return FAIL;
+		if (opt->jo_term_cols < 0 || opt->jo_term_cols > 1000)
+		{
+		    semsg(_(e_invalid_value_for_argument_str), "term_cols");
+		    return FAIL;
+		}
 	    }
 	    else if (STRCMP(hi->hi_key, "vertical") == 0)
 	    {