Fix array out of bounds read.

[Mictronics]

Causes lately a warning:
src/modules/AdminModule.cpp:355:18: warning: iteration 4 invokes undefined behavior [-Waggressive-loop-optimizations]

sizeof(r->get_module_config_response.payload_variant.remote_hardware.available_pins);will return a value of 80.
meshtastic_RemoteHardwarePin available_pins[4]; = (4+15+1) * 4

Someone more familiar with this part of code please check if available_pins_countis what we want here.

[Mictronics]

Got this error one time only on first reboot after flashing the fix.

ERROR | ??:??:?? 18 [Router] Can't decode protobuf reason='invalid wire_type', pb_msgdesc 0x10080c5c
ERROR | ??:??:?? 18 [Router] Error decoding protobuf module!
ERROR | ??:??:?? 18 [Router] Can't decode protobuf reason='invalid wire_type', pb_msgdesc 0x10080c5c
ERROR | ??:??:?? 18 [Router] Error decoding protobuf module!

Following reboots are all clean.

[thebentern]

Good find.