CA8210 driver drops some fragmented packets

[mtusnio]

I haven't found a way to reproduce this 100% of the time, but using this example client - https://github.com/FlowM2M/AwaLWM2M/blob/master/doc/example_app_static_api.md#example-create-a-standalone-lwm2m-client-within-a-contiki-environment - we've found that in some cases the bootstrap packet (containing the IP, [PublicKey], [SecretKey]) gets received but dropped by the driver. This is possibly due to fragmentation and timing of the packet arrival, and from what I've seen the radio usually receives one 104 byte packet. If data gets trimmed to fit into one packet the issue disappears.

[abhijit-mahajani-imgtec]

Need to check with latest cascoda driver on linux, since its observed between Ci40 and clickers.