Two fixes for the 'saa7146_wait_for_debi_done' code:
(a) Timeout did not work when the routine was called with
interrupts disabled.
(b) Reduce PCI I/O load caused by saa7146_wait_for_debi_done.
Seems to be very important on fast machines!
Based on code posted by Hartmut Birr @vdr-portal.
Signed-off-by: Oliver Endriss <o.endriss@gmx.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>