Net of rewriting vppapigen in python-ply, there's no need to compile
vppinfra.
Install a copy of vppapigen in .../build-root/tools/bin, so
the sample plugin build will work. Rationalize suffix-rules.mk.
Add clang, clang++ links to .../build-root/ccache-bin.
Change-Id: Ib4017848b7767b6054238ea544ee5319667c3659
Signed-off-by: Dave Barach <dave@barachs.net>
