We need to add "clean-files" in Makfiles to clean up DT blobs, but we
often miss to do so.

Since there are no source files that end with .dtb or .dtb.S, so we
can clean-up those files from the top-level Makefile.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NRob Herring <robh@kernel.org>

The current rules have the .dtb files build in a different directory
from the .dts files. This patch changes openrisc to use the generic dtb
rule which builds .dtb files in the same directory as the source .dts.

This requires renaming arch/openrisc/boot/Makefile to
arch/openrisc/boot/dts/Makefile, and updating arch/openrisc/Makefile to
call the new Makefile.

Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

This hooks dtc into Kbuild's dependency system.

Thus, for example, "make dtbs" will rebuild tegra-harmony.dtb if only
tegra20.dtsi has changed yet tegra-harmony.dts has not. The previous
lack of this feature recently caused me to have very confusing "git
bisect" results.

For ARM, it's obvious what to add to $(targets). I'm not familiar enough
with other architectures to know what to add there. Powerpc appears to
already add various .dtb files into $(targets), but the other archs may
need something added to $(targets) to work.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
[mmarek: Dropped arch/c6x part to avoid merging commits from the middle
of the merge window]
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Signed-off-by: NJonas Bonn <jonas@southpole.se>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>