ssb: Fix SPROM writing

The SPROM writing routines were broken since we rewrote the suspend
handling on wireless devices, because SPROM writing depended on suspend.

This patch changes it and freezes devices with the driver remove(), probe()
callbacks instead. This also simplifies the whole logics a lot.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>