cpu: Check the KVM API version with a static_assert instead of macros.
cpu: Check the KVM API version with a static_assert instead of macros.

Change-Id: Id8d52e25c4582ad802ee59facad5a1c31c2aa216
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/45743
Reviewed-by: Andreas Sandberg <c9f5686ee5bd561c93f9de79681eee75bfa7f36e@arm.com>
Reviewed-by: Daniel Carvalho <91779fc734d358d9575ec4910de29bfcbcaf1b22@yahoo.com.br>
Maintainer: Andreas Sandberg <c9f5686ee5bd561c93f9de79681eee75bfa7f36e@arm.com>
Tested-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>

gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5