Format the caching-mode option for the intel-iommu device,
based on its <driver caching> attribute value.
https://bugzilla.redhat.com/show_bug.cgi?id=1427005
---
src/qemu/qemu_capabilities.c | 2 ++
src/qemu/qemu_capabilities.h | 1 +
src/qemu/qemu_command.c | 11 ++++++++++
tests/qemucapabilitiesdata/caps_2.9.0.x86_64.xml | 1 +
.../qemuxml2argv-intel-iommu-caching-mode.args | 25 ++++++++++++++++++++++
tests/qemuxml2argvtest.c | 11 ++++++++++
6 files changed, 51 insertions(+)
create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-intel-iommu-caching-mode.args