Changes

Makefile: re-generate per-suite Makefile(s) if needed

Make per-suite Makefile depend on scripts generating it, so that
make will re-generate Makefile if any of its scripts has changed.
Otherwise, Makefile(s) are not re-generated automatically.

Change-Id: I8b73bf8e4c2f6e008eab9581f8c6840b22a5bd6a