acorn/fd1772: replace sleep_on() with wait_event()

@@ -139,6 +139,7 @@
 #include <linux/delay.h>
 #include <linux/mm.h>
 #include <linux/bitops.h>
+#include <linux/wait.h>
 
 #include <asm/arch/oldlatches.h>
 #include <asm/dma.h>

@@ -1283,8 +1284,7 @@ static void do_fd_request(request_queue_
 	if (fdc_busy) return;
 	save_flags(flags);
 	cli();
-	while (fdc_busy)
-		sleep_on(&fdc_wait);
+	wait_event(fdc_wait, !fdc_busy);
 	fdc_busy = 1;
 	ENABLE_IRQ();
 	restore_flags(flags);