Add the SD-Mapper v2 driver amongst the default drivers

[sdsnatcher]

The SD-Mapper v2 driver is very stable. Could you please include in amongst the default drivers that are build when every new version of Nextor is released?

The driver can be obtained here:
https://github.com/fbelavenuto/msxsdmapperv2/tree/master/Driver

[Konamiman]

Hi, sure, I can include the SD-Mapper driver in the repository, provided that I get a pull request that introduces the driver source file in a new folder inside src/kernel/drivers and modifies the kernel Makefile to include the new driver in the build process. Note that as part of the build process all the assembler source files, including drivers, are assembled with Nestor80; thus the existing driver source might need some changes to make it Nestor80-friendly. Feel free to ask me if you have any doubts about how to do all of this.