pkg/test-libc_fifo_pipe: ignore Ipc_error messages

Such messages can occur by chance when killing 'echo' while the program
blocks in an IPC call. It gets killed nevertheless. So the message does
not hint at a failure of the test.

repos/libports/recipes/pkg/test-libc_fifo_pipe/runtime

@@ -2,7 +2,6 @@
 
 	<fail after_seconds="120"/>
 	<succeed>--- test succeeded ---</succeed>
-	<fail>Error: </fail>
 
 	<content>
 		<rom label="fs_rom"/>