Integrate LR1110 and mbed-os

I want t use LR1110 as the LoRa driver for the lorawan example code. I have added the LR1110 driver in mbed-os\connectivity\drivers\lora folder. A pull request for the same was added to the mbed-os and link is given below.
https://github.com/ARMmbed/mbed-os/pull/14560
I am using MBED CLI2 to compile and added STM32WB55RGV6 as a custom target (Custom target addition and compilation was successful). I modified the lora_radio_helper.h file to include the lr1110 driver. The file is attached.
[lora_radio_helper.txt](https://github.com/ARMmbed/mbed-os-example-lorawan/files/6375212/lora_radio_helper.txt)

I am getting compilation error as attached.

Start by reviewing the LR1110 driver added under mbed-os/connectivity/drivers/lora and the attached lora_radio_helper.h file, then reproduce the reported compilation error with the STM32WB55RGV6 custom target using Mbed CLI 2. Check the linked mbed-os pull request for the current state of the driver work. Done means the LoRaWAN example compiles with LR1110 selected as its radio driver.

Written by the indexing model from the issue text.