Compilation with actual makefile fails with MinGW 11.2 64 Bit on Windows 10

[Ulibaer]

The compilation with actual makefile fails with MinGW 11.2 64 Bit on Windows 10, because it does not find compiler executable.

The following patch resolves this - at least on my system:

399a400
> 	ifeq ($(KERNEL),Linux)
411a413,415
> 	endif
> 	else
> 		CXX=g++

The former makefiles to at least 14.1 worked without issue. I used the old makefiles to find the position of the error and to generate the patch.