Switch to ansi build (Closes: #909442)

Due to the changes brought with 70_fix-parallel-build.patch, all builds
but arm64 worked. Arm64 build failed because of ans2knr executable
producing random wrong prototypes. I saw this was due to an unsafe use of
strcpy that most of the time works but not on arm64.
Actually, conversion of ansi to knr standard is not necessary as cc is
ansi. So we can :
- use the ansi build makefile
- get of rid the parallel build fix that is needed only in the unix
build because of ansi2knr use, which we avoid in the ansi build