Allow the nvmupdate application to decide when a read or write error
should be exposed to the user.  Since the application needs to use
write probes to find the ReadOnly sections on a potentially unknown NVM
version in the HW and read probes to check the status of the last write,
some error messages are expected, but need not be shown to the users.
The driver doesn't know which are ignorable from real errors, so needs
to let the application make the decision.

Change-ID: I78fca8ab672bede11c10c820b83c26adfd536d03
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>