Under musl a compilation unit cannot include both linux/kernel.h
and sys/sysinfo.h at the same time since that leads to a redefinition
of `struct sysinfo`.

Change the autoconf template to include linux/kernel.h while testing
for sys/sysinfo.h to test for that conflict.

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

Remove 001-cross_compile.patch, it's fixed upstream (ZBX-5561)
Run tested on ar71xx

Signed-off-by: Etienne CHAMPETIER <champetier.etienne@gmail.com>

Signed-off-by: Christoph König <christoph.koenig@gmail.com>
Signed-off-by: Etienne CHAMPETIER <champetier.etienne@gmail.com>

Signed-off-by: Etienne CHAMPETIER <champetier.etienne@gmail.com>

Signed-off-by: Etienne CHAMPETIER <etienne.champetier@free.fr>