This patch substantially revamps the dtc Makefiles, in particular
better integrating the Makefile for dtc proper with the Makefiles
imported from libfdt for libfdt and the shared testsuite. Notable
changes:
- No recursive make calls. Instead subsidiary Makefiles are
included into the top-level Makefile so we get a complete dependency
information.
- Common pattern rules, CFLAGS etc. shared between dtc, libfdt
and testsuite, rather than separate copies.
- Vaguely Kbuild-like non-verbose mode used by default, which
makes warnings more prominent.
- libfdt Makefile consists only of variable definitions and
helper rules, to make it more easily embeddable into other Makefile
systems.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>