cpuid: Don't test qemu64 with rhel6 machine-types on RHEL7 or unknown hosts

Signed-off-by: NEduardo Habkost <ehabkost@raisama.net>

qemu/tests/cfg/qemu_cpu.cfg

@@ -361,6 +361,12 @@
                         # KVM features depend on host kernel, as well:
                         ignore_cpuid_leaves += " 0x40000001,0,eax"
 
+                    machine.rhel.rhel6:
+                        cpu.amd.qemu64:
+                            # RHEL-7 doesn't keep the ABI for rhel6.* + qemu64
+                            no (qemu_flavor = rhel)..(rhel_major_version = 7)
+                            no (qemu_flavor = unknown)
+
                     # SEP bit depended on host kernel on 6.3 and older:
                     machine.rhel.rhel6.rhel630, machine.rhel.rhel6.rhel620, machine.rhel.rhel6.rhel610, machine.rhel.rhel6.rhel600:
                         ignore_cpuid_leaves += " 1,0,edx,11"