Autobaud for HL 8548

Unfortunately, the combination of no autobaud and a baud rate of 115.2 kbaud is a huge problem for applications where the host MCU is running at 8, 10, 16, 20 MHz, as the baud error rate is so high that one cannot reliably expect the command to be read by the module.

This leaves one with the problem of having to reconfigure the modem baud rate externally with another device, or of being limited to an MCU crystal frequency of 14.745 MHz for example.

If Sierra had chosen another default baud rate, this problem would not have arisen.

This problem is holding me up right now.