kvm tools: Fix absence of notrace definition

Ingo reported a build breakage caused by absence of 'notrace' definition. Fix
it by adding compiler.h into own headers set.

Reported-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>