devkitSMS for SDCC 4.1.x - frozen at 2022-05-05

This is a snapshot of the last version of devkitSMS to be compiled with and to use SDCC 4.1.x (up until 4.1.11 included)
Will be known as the 1.2 version, a.k.a. the 'old SDCC calling conventions' version.