uniq: plug memory leak (patch from OpenWRT project)

function                                             old     new   delta
uniq_main                                            371     389     +18

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

coreutils/uniq.c

@@ -89,6 +89,7 @@ int uniq_main(int argc UNUSED_PARAM, char **argv)
 				break;
 			}
 
+			free(cur_line);
 			++dups;	 /* testing for overflow seems excessive */
 		}