Add QEMU_CAPS_DEVICE_INTEL_IOMMU

Check whether QEMU supports -device intel-iommu

Note that the presence of this option does not mean that it's
usable because of a bug in earlier QEMU versions, but it's
better than nothing.

https://bugzilla.redhat.com/show_bug.cgi?id=1235580

src/qemu/qemu_capabilities.c

@@ -338,6 +338,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
 
               "tls-creds-x509", /* 230 */
               "display",
+              "intel-iommu",
     );
 
 
@@ -1564,6 +1565,7 @@ struct virQEMUCapsStringFlags virQEMUCapsObjectTypes[] = {
     { "pxb", QEMU_CAPS_DEVICE_PXB },
     { "pxb-pcie", QEMU_CAPS_DEVICE_PXB_PCIE },
     { "tls-creds-x509", QEMU_CAPS_OBJECT_TLS_CREDS_X509 },
+    { "intel-iommu", QEMU_CAPS_DEVICE_INTEL_IOMMU },
 };
 
 static struct virQEMUCapsStringFlags virQEMUCapsObjectPropsVirtioBalloon[] = {

src/qemu/qemu_capabilities.h

@@ -371,6 +371,7 @@ typedef enum {
     /* 230 */
     QEMU_CAPS_OBJECT_TLS_CREDS_X509, /* -object tls-creds-x509 */
     QEMU_CAPS_DISPLAY, /* -display */
+    QEMU_CAPS_DEVICE_INTEL_IOMMU, /* -device intel-iommu */
 
     QEMU_CAPS_LAST /* this must always be the last item */
 } virQEMUCapsFlags;

tests/qemucapabilitiesdata/caps_2.4.0.x86_64.xml

@@ -182,6 +182,7 @@
   <flag name='spice-unix'/>
   <flag name='drive-detect-zeroes'/>
   <flag name='display'/>
+  <flag name='intel-iommu'/>
   <version>2004000</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.5.0.x86_64.xml

@@ -187,6 +187,7 @@
   <flag name='drive-detect-zeroes'/>
   <flag name='tls-creds-x509'/>
   <flag name='display'/>
+  <flag name='intel-iommu'/>
   <version>2005000</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.6.0.x86_64.xml

@@ -193,6 +193,7 @@
   <flag name='drive-detect-zeroes'/>
   <flag name='tls-creds-x509'/>
   <flag name='display'/>
+  <flag name='intel-iommu'/>
   <version>2006000</version>
   <kvmVersion>0</kvmVersion>
   <package></package>