Read back Status Register 1 to ensure that the written byte match the
received value and return -EIO if read back test failed.
Without this patch, spi_nor_write_16bit_sr_and_check() only check the
second half of the 16bit. It causes errors like spi_nor_sr_unlock()
return success incorrectly when spi_nor_write_16bit_sr_and_check()
doesn't write SR successfully.
Fixes: 39d1e3340c73 ("mtd: spi-nor: Fix clearing of QE bit on lock()/unlock()")
Signed-off-by: Chen-Tsung Hsieh <chentsung@xxxxxxxxxxxx>