build: add ccache for cross compilation

build: add ccache for cross compilation

By default, ccache is not used for cross build[1].
Update all cross files to use ccache if it is available
in build machine.

Also, updated devtools/test-meson-builds.sh
script to find the correct DPDK_TARGET due to
change in cross file syntax.

[1]
https://mesonbuild.com/Machine-files.html

Signed-off-by: Jerin Jacob <jerinj@marvell.com>
Acked-by: Stanislaw Kardach <kda@semihalf.com>
Acked-by: Chengwen Feng <fengchengwen@huawei.com>
Acked-by: Ruifeng Wang <ruifeng.wang@arm.com>