container: expose priority and SCHED_OTHER policy

The more explicit API removes the arbitrary limit preventing use of SCHED_OTHER (referred to as SCHED_NORMAL in the kernel). This change also exposes priority value to set.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/mbf/main.go

@@ -87,7 +87,7 @@ func main() {
 		}
 
 		if flagIdle {
-			pkg.SchedPolicy = std.SCHED_IDLE
+			pkg.SetSchedIdle = true
 		}
 
 		return