cli: add 'ioapic.driver' to --features

Add the ability to set the ioapic driver using the --features argument:

    $ virt-install --features ioapic.driver=qemu ...

This results in the following xml:

  <features>
    ...
    <ioapic driver="qemu"/>
  </features>

This is required in order to install a guest with >255 cpus. Such a
configuration requires an iommu with extended interrupt mode enabled,
which in turn requires IOMMU interrupt remapping to be enabled, which in
turn requires a split I/O APIC.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>

tests/data/cli/compare/virt-install-singleton-config-3.xml

@@ -74,6 +74,7 @@
     <pvspinlock state="off"/>
     <smm state="off"/>
     <vmcoreinfo state="on"/>
+    <ioapic driver="qemu"/>
   </features>
   <cpu>
     <topology sockets="1" dies="1" cores="3" threads="2"/>

tests/data/xmlparse/change-guest-out.xml

@@ -32,6 +32,7 @@
       <hidden state="on"/>
     </kvm>
     <pvspinlock state="on"/>
+    <ioapic driver="qemu"/>
   </features>
   <numatune>
     <memory nodeset="2,4,6"/>

tests/test_cli.py

@@ -576,7 +576,7 @@ c.add_compare("""
 --vcpus vcpu.current=3,maxvcpus=4,vcpu.placement=auto
 --memory hotplugmemorymax=2048,hotplugmemoryslots=2
 --disk none
---features apic.eoi=off,hap=on,hyperv.synic.state=on,hyperv.reset.state=off,hyperv.spinlocks.state=on,hyperv.spinlocks.retries=5678,pae=on,pmu.state=on,pvspinlock.state=off,smm.state=off,viridian=on,vmcoreinfo.state=on,vmport.state=off,kvm.hidden.state=on,hyperv.vapic.state=off,hyperv.relaxed.state=off,gic.version=host,kvm.hint-dedicated.state=on,kvm.poll-control.state=on
+--features apic.eoi=off,hap=on,hyperv.synic.state=on,hyperv.reset.state=off,hyperv.spinlocks.state=on,hyperv.spinlocks.retries=5678,pae=on,pmu.state=on,pvspinlock.state=off,smm.state=off,viridian=on,vmcoreinfo.state=on,vmport.state=off,kvm.hidden.state=on,hyperv.vapic.state=off,hyperv.relaxed.state=off,gic.version=host,kvm.hint-dedicated.state=on,kvm.poll-control.state=on,ioapic.driver=qemu
 --clock rtc_present=no,pit_present=yes,pit_tickpolicy=catchup,tsc_present=no,platform_present=no,hypervclock_present=no,platform_tickpolicy=foo,hpet_tickpolicy=bar,tsc_tickpolicy=wibble,kvmclock_tickpolicy=wobble,hypervclock_tickpolicy=woo
 --boot bios.useserial=no,bios.rebootTimeout=60,cmdline=root=/foo,smbios.mode=host,bootmenu.enable=yes,bootmenu.timeout=5000,loader_ro=yes,loader.type=rom,loader=/tmp/foo
 --memorybacking access.mode=shared,source.type=anonymous,hugepages=on

tests/test_xmlparse.py

@@ -162,6 +162,7 @@ def testAlterGuest():
     check("kvm_hidden", None, True)
     check("pvspinlock", None, True)
     check("gic_version", None, False)
+    check("ioapic_driver", None, "qemu")
 
     check = _make_checker(guest.cpu)
     check("match", "exact", "strict")

virtinst/cli.py

@@ -2965,6 +2965,7 @@ class ParserFeatures(VirtCLIParser):
 
         cls.add_arg("smm.state", "smm", is_onoff=True)
         cls.add_arg("vmcoreinfo.state", "vmcoreinfo", is_onoff=True)
+        cls.add_arg("ioapic.driver", "ioapic_driver")
 
 
 ###################

virtinst/domain/features.py

@@ -42,6 +42,7 @@ class DomainFeatures(XMLBuilder):
 
     smm = XMLProperty("./smm/@state", is_onoff=True)
     vmcoreinfo = XMLProperty("./vmcoreinfo/@state", is_onoff=True)
+    ioapic_driver = XMLProperty("./ioapic/@driver")
 
 
     ##################