Remove restriction on ISO partition types

This is not a valid way to detect installation media, but it is a way
that config data can be provided to the host during a CAPI install.

For a full ISO the current install media partitions look like this:

```
[root@localhost core]# fdisk -l /dev/sr0
Disk /dev/sr0: 1.16 GiB, 1244659712 bytes, 607744 sectors
Disk model: QEMU DVD-ROM
Units: sectors of 1 * 2048 = 2048 bytes
Sector size (logical/physical): 2048 bytes / 2048 bytes
I/O size (minimum/optimal): 2048 bytes / 2048 bytes
Disklabel type: dos
Disk identifier: 0x47ad035f

Device     Boot Start     End Sectors  Size Id Type
/dev/sr0p1 *        0 2430975 2430976  4.6G  0 Empty
/dev/sr0p2        180   10139    9960 19.5M ef EFI (FAT-12/16/32)
```

Neither of these partitions are of type iso9660 so this check is doing
nothing but making CAPI installs more difficult.

src/inventory/disks.go

@@ -360,15 +360,6 @@ func (d *disks) checkEligibility(disk *ghw.Disk) (notEligibleReasons []string, i
 
 	// Check disk partitions for type, name, and mount points:
 	for _, partition := range disk.Partitions {
-		if partition.Type == "iso9660" {
-			notEligibleReasons = append(
-				notEligibleReasons,
-				"Disk appears to be an ISO installation media (has partition with "+
-					"type iso9660)",
-			)
-			isInstallationMedia = true
-		}
-
 		if strings.HasSuffix(partition.MountPoint, "iso") {
 			notEligibleReasons = append(
 				notEligibleReasons,

src/inventory/disks_test.go

@@ -550,7 +550,7 @@ var _ = Describe("Disks test", func() {
 	})
 
 	It("filters ISO disks / marks them as installation media", func() {
-		blockInfo, expectedDisks := prepareDisksTest(dependencies, 3)
+		blockInfo, expectedDisks := prepareDisksTest(dependencies, 2)
 
 		blockInfo.Disks[0].Partitions = []*ghw.Partition{
 			{
@@ -569,27 +569,9 @@ var _ = Describe("Disks test", func() {
 		}
 		expectedDisks[0].IsInstallationMedia = true
 
-		blockInfo.Disks[1].Partitions = []*ghw.Partition{
-			{
-				Disk:       nil,
-				Name:       "partition2",
-				Label:      "partition2-label",
-				MountPoint: "/some/mount/point",
-				SizeBytes:  5555,
-				Type:       "iso9660",
-				IsReadOnly: false,
-			},
-		}
-
-		expectedDisks[1].InstallationEligibility.Eligible = false
-		expectedDisks[1].InstallationEligibility.NotEligibleReasons = []string{
-			"Disk appears to be an ISO installation media (has partition with type iso9660)",
-		}
-		expectedDisks[1].IsInstallationMedia = true
-
 		// Make sure regular disks don't get marked as installation media
-		expectedDisks[2].InstallationEligibility.Eligible = true
-		expectedDisks[2].IsInstallationMedia = false
+		expectedDisks[1].InstallationEligibility.Eligible = true
+		expectedDisks[1].IsInstallationMedia = false
 
 		mockFetchDisks(dependencies, nil, blockInfo.Disks...)
 		ret := GetDisks(&config.SubprocessConfig{}, dependencies)