insert TGTBINMK variable in Makefile.inc
insert TGTBINMK variable in Makefile.inc

So sourcing this file allows to determine transparently
type of compilation.

ucam-smt/ucam-smt,ucam-smt/ucam-smt,ucam-smt/ucam-smt,ucam-smt/ucam-smt,ucam-smt/ucam-smt,ucam-smt/ucam-smt