qemu: set the cpu type to max

RHEL9 and therefore the dependent distributions and base containers have
a minimum microarchitechture level of x86-64-v2.[1]

The default cpu level of the qemu driver on an Intel Mac is x86-64-v1
even if the host cpu has the x86-64-v2 capability. Using the cpu type of
max allows qemu to use all the host cpu capabilities that is also
supported by the hypervisor framework.[2]

This was fixed for linux host by changing the default within qemu but it
wasn't changed for MacOS.

[1] https://developers.redhat.com/blog/2021/01/05/building-red-hat-enterprise-linux-9-for-the-x86-64-v2-microarchitecture-level
[2] https://gitlab.com/qemu-project/qemu/-/issues/1686#note_1417714887
[3] https://lists.gnu.org/archive/html/qemu-devel/2022-08/msg04066.html

Signed-off-by: Raghavendra Talur <raghavendra.talur@gmail.com>

pkg/minikube/registry/drvs/qemu2/qemu2.go

@@ -125,7 +125,9 @@ func configure(cc config.ClusterConfig, n config.Node) (interface{}, error) {
 	switch runtime.GOARCH {
 	case "amd64":
 		qemuMachine = "" // default
-		qemuCPU = ""     // default
+		// set cpu type to max to enable higher microarchitecture levels
+		// see https://lists.gnu.org/archive/html/qemu-devel/2022-08/msg04066.html for details
+		qemuCPU = "max"
 	case "arm64":
 		qemuMachine = "virt"
 		qemuCPU = "cortex-a72"