package/sysdig: New package

Sysdig is open source, system-level exploration: capture system state
and activity from a running Linux instance, then save, filter and
analyze.

[Thomas:
 - remove unneeded 0001-makefile-driver-compile-options.patch, instead
   pass KERNELDIR in the make options when building the driver, and
   pass the contents of $(LINUX_MAKE_FLAGS) directly.
 - use $(SYSDIG_BUILDDIR) instead of $(@D)/buildroot-build, so that
   the package does not depend on the package infra using specifically
   buildroot-build as the build subdirectory.
 - use $(MAKE) -C <foo> instead of cd <foo>; $(MAKE).
 - rename 0002 patch to 0001, since the 0001 patch is removed.]

Signed-off-by: Angelo Compagnucci <angelo.compagnucci@gmail.com>
Reviewed-by: Yegor Yefremov <yegorslists@googlemail.com>
Reviewed-by: Ryan Barnett <ryan.barnett@rockwellcollins.com>
Tested-by: Ryan Barnett <ryan.barnett@rockwellcollins.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>