* ccache is now a normal package (both for the host and the target).
* ccache option is now part of the "Build options" menu. It will
automatically build ccache for the host before building anything,
and will use it to cache builds for both host compilations and
target compilations.
* bump ccache to 3.1.3
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
