Re: [libvirt PATCH v3 00/25] introduce external snapshot revert support

This implements virDomainRevertToSnapshot to work with external snapshots. In addition it modifies virDomainSnapshotDelete to work correctly when we revert to non-leaf snapshot or when there is non-linear snapshot tree with multiple branches. Gitlab repo with the patches: https://gitlab.com/hrdina/libvirt/-/tree/snapshot-revert-external changes in v3: - `revertdisks` is properly freed in virDomainSnapshotDefDispose() - qemuSnapshotCreateQcow2Files() no longer takes `reuse` as argument and was changed to take `virDomainDef *` instead of `virDomainObj *` - proper commit message for `qemu_snapshot: use VIR_ASYNC_JOB_SNAPSHOT when reverting snapshot` - fixed incorrect usage of `ssize_t i` - dropped the weird logic from qemuSnapshotRevertExternalInactive() as we only need offline VM definition and preserve correct error message if creating qcow files fails - qemuSnapshotClearRevertdisks() correctly frees `revertdisks` - added new patches 'qemuDomainGetImageIds: pass domain definition directly` as we need to modify the function to take `virDomainDef *` directly - qemuSnapshotDiskHasBackingDisk() now uses qemuDomainGetImageIds() to get correct UID and GID for virStorageSourceGetMetadata() and also for virCommandRun() as well by storing it in `struct _qemuSnapshotDisksWithBackingStoreData`