ljsyscall: new package

An FFI implementation of the Linux and NetBSD kernel ABIs for LuaJIT.

Signed-off-by: Danomi Manchego <danomimanchego123@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
luajit: refactor without dont-strip.patch

the variable TARGET_STRIP does the job
luajit: refactor without shared-lib.patch

the variable BUILDMODE does the job