strace: use bundled kernel headers

strace: use bundled kernel headers

Build against the bundled kernel headers instead of using the current
kernel ones. This ensures strace is using the kernel headers it is
written against, and not a random one that may contain breaking uapi
changes (which happen from time to time).

Fixes build against 6.18 final and recent LTS/stable kernels that got
minor uapi breakages (rename of a 6.18 introduced #define and a struct
field).

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>