support/scripts: add script to test a package

This script helps in testing that a package builds fine on a wide range
of architectures and toolchains: BE/LE, 32/64-bit, musl/glibc/uclibc...

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
[yann.morin.1998@free.fr:
 - completely rewrite the script from Thomas, with help from Luca
]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Luca Ceresoli <luca@lucaceresoli.net>
Cc: Thomas De Schampheleire <patrickdepinguin@gmail.com>
Acked-by: Luca Ceresoli <luca@lucaceresoli.net>
Reviewed-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Tested-by: Luca Ceresoli <luca@lucaceresoli.net>
Acked-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>