Staging: b3dfg: fix sched.h build breakage

commit d43c36dc removed sched.h from interrupt.h.  This broke the
b3dfg driver.  This patch fixes this.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/b3dfg/b3dfg.c b/drivers/staging/b3dfg/b3dfg.c
index 94c5d27..cda26bb 100644
--- a/drivers/staging/b3dfg/b3dfg.c
+++ b/drivers/staging/b3dfg/b3dfg.c
@@ -36,6 +36,7 @@
 #include <linux/wait.h>
 #include <linux/mm.h>
 #include <linux/uaccess.h>
+#include <linux/sched.h>
 
 static unsigned int b3dfg_nbuf = 2;