Change default CPU type to kvm64 with smep/smap

Author: gsingh93

Makefile

@@ -330,7 +330,7 @@ endif
 ifeq ($(ARCH),x86_64)
   QEMU_BIN := qemu-system-x86_64
   QEMU_ARGS += \
-    -cpu max \
+    -cpu kvm64,+smep,+smap \
     -append "8250.nr_uarts=1 console=ttyS0 selinux=0 kpti no5lvl $(QEMU_EXTRA_KERNEL_CMDLINE)"
 
   # We can't use KVM with GitHub Actions CI