drivers: fix support for U-Blox M10 modules with M8 driver

The U-Blox M10 seems to interleave UBX and NMEA messages in a way that
confuses the M8 driver leading to missing the same message that directly
follows the UBX part every time (leading to no navigation updates).
As the driver does not parse the UBX blocks during normal operation anyways
it can just be disabled.

Signed-off-by: Jakob Riepler <jakob+zephyr@chaosfield.at>