ssb: Handle Netbook devices where the SPROM address is changed

ssb: Handle Netbook devices where the SPROM address is changed

For some Netbook computers with Broadcom BCM4312 wireless interfaces,
the SPROM has been moved to a new location. When the ssb driver tries to
read the old location, the systems hangs when trying to read a
non-existent location. Such freezes are particularly bad as they do not
log the failure.

This patch is modified from commit
da1fdb02d9200ff28b6f3a380d21930335fe5429 with some pieces from other
mainline changes so that it can be applied to stable 2.6.34.Y.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>