[PATCH] dvb: core: fix race condition in FE_READ_STATUS ioctl

Fix a race condition where an application which issued a FE_READ_STATUS ioctl
directly after FE_SET_FRONTEND would see an old status, i.e.  FE_READ_STATUS
would be executed before the frontend thread has even seen the tungin request
from FE_SET_FRONTEND.

Signed-off-by: Peter Beutner <p.beutner@gmx.net>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>