Cleanup example data

These examples were crashing dryrun if supplied as a machineconfig due
to the missing blockdev.

examples/many-nics-and-disks.json

@@ -1,5 +1,10 @@
 {
     "storage": {
+        "bcache": {
+            "backing": {},
+            "caching": {}
+        },
+        "blockdev": {
             "/dev/sda": {
                 "DEVLINKS": "/dev/disk/by-path/pci-0000:00:01.1-ata-1 /dev/disk/by-id/ata-QEMU_HARDDISK_QM00001",
                 "DEVNAME": "/dev/sda",
@@ -599,6 +604,7 @@
                     "uevent": "MAJOR=253\nMINOR=1\nDEVNAME=dm-1\nDEVTYPE=disk"
                 }
             }
+        }
     },
     "network": {
         "links": [

examples/virtio.json

@@ -1,5 +1,10 @@
 {
     "storage": {
+        "bcache": {
+            "backing": {},
+            "caching": {}
+        },
+        "blockdev": {
             "/dev/sr0": {
                 "DEVLINKS": "/dev/dvd /dev/disk/by-uuid/2018-02-11-21-54-54-00 /dev/disk/by-path/pci-0000:00:01.1-ata-2 /dev/disk/by-id/ata-QEMU_DVD-ROM_QM00003 /dev/disk/by-label/Ubuntu\\x20custom\\x20amd64 /dev/cdrom",
                 "DEVNAME": "/dev/sr0",
@@ -124,6 +129,7 @@
                     "uevent": "MAJOR=2\nMINOR=0\nDEVNAME=fd0\nDEVTYPE=disk"
                 }
             }
+        }
     },
     "network": {
         "links": [