headers: remove sched.h from interrupt.h

After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
diff --git a/net/irda/irnet/irnet_irda.c b/net/irda/irnet/irnet_irda.c
index cf9a4b5..cccc2e9 100644
--- a/net/irda/irnet/irnet_irda.c
+++ b/net/irda/irnet/irnet_irda.c
@@ -9,6 +9,7 @@
  */
 
 #include "irnet_irda.h"		/* Private header */
+#include <linux/sched.h>
 #include <linux/seq_file.h>
 #include <asm/unaligned.h>