more -Wall warning fixes. -Wall is enabled now.

diff --git a/util-linux/more.c b/util-linux/more.c
index 257f401..2577a67 100644
--- a/util-linux/more.c
+++ b/util-linux/more.c
@@ -62,8 +62,8 @@
 	FILE *file;
 	FILE *cin;
 	int len;
-	int terminal_width;
-	int terminal_height;
+	unsigned terminal_width;
+	unsigned terminal_height;
 
 	INIT_G();