seccomp: Allow to copy and clone SeccompLevel
seccomp: Allow to copy and clone SeccompLevel

Since the enum SeccompLevel values are simple integers, it's safe and
convenient to be able to copy and clone its values. That's the reason
why this patch derives both Clone and Copy trait for the enum type
SeccompLevel.

Signed-off-by: Sebastien Boeuf <90b401417360b1924ef3f520ddee932686110f85@intel.com>

firecracker-microvm/firecracker,firecracker-microvm/firecracker,firecracker-microvm/firecracker,firecracker-microvm/firecracker,firecracker-microvm/firecracker