Long device names cause trouble

[amakuzaze]

The bluedroid stack accepted most device names I threw at it just fine, but nimble seems to have tighter restrictions. I'll investigate and update this issue as I go.

[amakuzaze]

My findings so far: Name is limited to 19 octets. The menuconfig entry appears to make this configurable (and also the 31 octets there aren't correct, since some of that payload length is used for flags and other management fields) but raising the limit currently does nothing.

Also see: apache/mynewt-nimble#835

[amakuzaze]

For reference: The menuconfig entry only affects the GAP attribute and has no influence over how the advertising / scan response packets are woven.