stty: fix columns command. closes bug 791.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/coreutils/stty.c b/coreutils/stty.c
index 0485b80..776a16a 100644
--- a/coreutils/stty.c
+++ b/coreutils/stty.c
@@ -1360,6 +1360,7 @@
 #endif
 #ifdef TIOCGWINSZ
 		case param_cols:
+		case param_columns:
 			set_window_size(-1, xatoul_sfx(argnext, stty_suffixes));
 			break;
 		case param_size: