Added bios type firmware support for loongarch64

Since the internal snapshot function of virt-manager
cannot be used when using UEFI firmware, the bios type
firmware is added to loongarch64. The bios type firmware
uses the QEMU_EFI.fd file and loads it with the -bios parameter.
This allows us to use virt-manager internal snapshots
while the virtual machine is on.

This also requires edk2 to have a corresponding json file in
/usr/share/qemu/firmware at installation time.
The file contents are as follows:

{
    "description": "LoongArch UEFI for loongarch64",
    "interface-types": [
        "bios"
    ],
    "mapping": {
        "device": "memory",
        "filename": "/usr/share/qemu/QEMU_CODE.fd"
    },
    "targets": [
        {
            "architecture": "loongarch64",
            "machines": [
                "virt*"
            ]
        }
    ],
    "features": [
        "acpi"
    ],
    "tags": [

    ]
}

Signed-off-by: Xianglai Li <[email protected]>
Signed-off-by: Xianglai Li <[email protected]>

virtManager/details/details.py

@@ -657,7 +657,11 @@ def _buf_changed_cb(*args):
                   "installed on the host."))
 
         # Put the default entry first in the list
-        model.append([domcaps.label_for_firmware_path(None), None, True, None])
+        if self.vm.get_arch() == "loongarch64":
+            model.append([domcaps.label_for_firmware_path(None), None, True, "bios"])
+        else:
+            model.append([domcaps.label_for_firmware_path(None), None, True, None])
+
         for row in uefirows:
             model.append(row)
         combo.set_active(0)

virtinst/domcapabilities.py

@@ -320,7 +320,7 @@ def label_for_firmware_path(self, path):
         about it or not
         """
         if not path:
-            if self.arch in ["i686", "x86_64"]:
+            if self.arch in ["i686", "x86_64", "loongarch64"]:
                 return _("BIOS")
             return _("Default")