qemu: caps: Introduce capability for 'device_id' property of 'scsi-disk'

The property allows to control the guest-visible content of the vendor
specific designator of the 'Device Identification' page of a SCSI
device's VPD (vital product data).

QEMU was leaking the id string of -drive as the value if the 'serial' of
the disk was not specified. Switching to -blockdev would impose an ABI
change.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

src/qemu/qemu_capabilities.c

@@ -524,6 +524,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
               /* 325 */
               "memory-backend-file.pmem",
               "nvdimm.unarmed",
+              "scsi-disk.device_id",
     );
 
 
@@ -1157,6 +1158,7 @@ static struct virQEMUCapsStringFlags virQEMUCapsDevicePropsSCSIDisk[] = {
     { "wwn", QEMU_CAPS_SCSI_DISK_WWN },
     { "share-rw", QEMU_CAPS_DISK_SHARE_RW },
     { "write-cache", QEMU_CAPS_DISK_WRITE_CACHE },
+    { "device_id", QEMU_CAPS_SCSI_DISK_DEVICE_ID },
 };
 
 static struct virQEMUCapsStringFlags virQEMUCapsDevicePropsIDEDrive[] = {

src/qemu/qemu_capabilities.h

@@ -504,6 +504,7 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */
     /* 325 */
     QEMU_CAPS_OBJECT_MEMORY_FILE_PMEM, /* -object memory-backend-file,pmem= */
     QEMU_CAPS_DEVICE_NVDIMM_UNARMED, /* -device nvdimm,unarmed= */
+    QEMU_CAPS_SCSI_DISK_DEVICE_ID, /* 'device_id' property of scsi disk */
 
     QEMU_CAPS_LAST /* this must always be the last item */
 } virQEMUCapsFlags;

tests/qemucapabilitiesdata/caps_4.0.0.x86_64.xml

@@ -209,6 +209,7 @@
   <flag name='memory-backend-file.align'/>
   <flag name='memory-backend-file.pmem'/>
   <flag name='nvdimm.unarmed'/>
+  <flag name='scsi-disk.device_id'/>
   <version>3001050</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>43100758</microcodeVersion>