LR1110 has codingRate as protected field in LR_common.h, so
getCodingRate() is implemented in CustomLR1110 class directly,
and exposed via CustomLR1110Wrapper override.
This enables dynamic MAX_TEXT_LEN calculation for T1000-E
under JP_STRICT mode.
it seems that if the LR1110 radio hears a packet corrupted in a specific way, it'll report a packet of 0 length and with the header error IRQ set. every packet received afterwards will then be shifted to the right by 4 bytes on top of the radio's reported offset. this can occur multiple times with the shift increasing by 4 bytes each time. thus, this patch will read from an additional offset after hearing the trigger packet.
transmitting seems to reset the shift - unsure exactly what operation resets it but standby() is called after tx so patch assumes shift is 0 after standby(). more investigation may be needed here.
