surface: surface3_power: Fix battery readings on batteries without a serial number

commit 21d90aae upstream.

The battery on the 2nd hand Surface 3 which I recently bought appears to
not have a serial number programmed in. This results in any I2C reads from
the registers containing the serial number failing with an I2C NACK.

This was causing mshw0011_bix() to fail causing the battery readings to
not work at all.

Ignore EREMOTEIO (I2C NACK) errors when retrieving the serial number and
continue with an empty serial number to fix this.

Fixes: b1f81b49 ("platform/x86: surface3_power: MSHW0011 rev-eng implementation")
BugLink: https://github.com/linux-surface/linux-surface/issues/608


Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220224101848.7219-1-hdegoede@redhat.com


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