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/drivers/net/skfp/skfddi.c b/drivers/net/skfp/skfddi.c
index 38a508b..b27156eaf 100644
--- a/drivers/net/skfp/skfddi.c
+++ b/drivers/net/skfp/skfddi.c
@@ -73,6 +73,7 @@
 
 /* Include files */
 
+#include <linux/capability.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>