UBUNTU: SAUCE: rtsx_usb_ms: Use msleep_interruptible() in polling loop

BugLink: http://bugs.launchpad.net/bugs/1413149

rtsx_usb_ms creates a task that mostly sleeps, but tasks in
uninterruptible sleep still contribute to the load average (for
bug-compatibility with Unix).  A load average of ~1 on a system that
should be idle is somewhat alarming.

Change the sleep to be interruptible, but still ignore signals.

A better fix might be to replace this loop with a delayed work item.

References: https://bugs.debian.org/765717Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Chris J Arges <chris.j.arges@canonical.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>

drivers/memstick/host/rtsx_usb_ms.c

@@ -706,7 +706,8 @@ static int rtsx_usb_detect_ms_card(void *__host)
 		if (host->eject)
 			break;
 
-		msleep(1000);
+		if (msleep_interruptible(1000))
+			flush_signals(current);
 	}
 
 	complete(&host->detect_ms_exit);