Previously, the CI Makefile used kldload -n vmm to determine whether the host supported bhyve virtualization. However, due to changes in how QEMU/KVM exposes CPU features to guests, this check no longer reliably indicates the presence of usable VMX/SVM support.

In particular, modern QEMU configurations expose the vmx CPUID bit by default, allowing the vmm module to load even when nested virtualization is disabled. This causes the old check to incorrectly succeed inside virtualized environments where bhyve cannot function.

This patch replaces the check with a sysctl-based approach that inspects kern.vm_guest. If the system identifies itself as running inside a guest (!= "none"), we assume nested virtualization is unavailable and fallback to QEMU.

This change ensures CI behaves correctly on platforms where the vmm module loads but is not usable.