Staging: sep: Fix crash if a device is not found

The existing code works mostly by luck. The PCI probe is done by the
register and completes before the register returns thus allowing the other
init code to run in time. Without a SEP or if unlucky this doesn't occur
and you get an OOPS which for some reason causes grumpiness.

As the season of good b^Hcheer is supposed to be approaching we should
probably fix it.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>