misc: at25: Unshadow error codes in at25_fw_to_chip()

device_property_read_u32() may return different error codes.
Unshadow them in the at25_fw_to_chip() to give better error
report.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211125213203.86693-3-andriy.shevchenko@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>