Adjust the rhel documentation to refer to the supported OS file (#734)

* fix merge conflicts
Signed-off-by: Moath Qasim <[email protected]>

Signed-off-by: Moath Qasim <[email protected]>

* fix the documentation for rhel in vsphere
Signed-off-by: Moath Qasim <[email protected]>

Signed-off-by: Moath Qasim <[email protected]>

Author: moadqassem

docs/rhel-custom-image.md

@@ -13,7 +13,7 @@ Cloud providers which are listed below, support using rhel as an operating syste
 For amazon web service cloud provider, First of all the RHEL gold image AMIs have to be enabled from the 
 [RedHat Customer Portal](https://access.redhat.com/public-cloud/aws) (this requires a [cloud-provider subscription](https://access.redhat.com/public-cloud)).
 .Afterwards, new images will be added to the aws account under EC2-> Images-> AMIs-> Private Images. Once the images are available in the aws account, 
-the image id for rhel(at the moment we only support 8.x.x versions) should be then added to the `MachineDeployment` spec to the field `ami`.
+the image id for rhel(supported versions are mentioned [here](https://github.com/kubermatic/machine-controller/blob/master/docs/operating-system.md)) should be then added to the `MachineDeployment` spec to the field `ami`.
 
 ####  Azure
 RedHat provides images for Azure, [documentation](https://access.redhat.com/articles/uploading-rhel-image-to-azure) is available on RH customer portal.
@@ -47,9 +47,8 @@ image to vSphere, follow these steps to create instances from a cloned machine:
 
 - Download Red Hat Enterprise Linux 8.x KVM Guest Image from Red Hat Customer Portal.
 - The image has the format `qcow2` thus should be converted to `vmdk` by running the command: `qemu-img convert -f qcow2 rhel.qcow2 -O vmdk newRHEL.vmdk`
-- Run `vmkfstools -i myImage.vmdk outputName.vmdk -d thin To ensure that the` to ensure that, the `vmdk` is ESXi compatible.
 - Upload the image to vSphere Datastore. Preferably use [`govc`](https://github.com/vmware/govmomi/blob/master/govc/USAGE.md#datastoreupload)
-- Once the image is uploaded create a new instance using that image. During the machine creation process, at the `Customize Hardware`
-step, press on ADD NEW DEVICE and select Existing Hard Disk. 
+- Once the image is uploaded to ESXi host, run `vmkfstools -i newRHEL.vmdk outputRHEL.vmdk -d thin`to ensure that, the `vmdk` image is ESXi compatible.
+- Create a new instance using that image. During the machine creation process, at the `Customize Hardware` step, press on ADD NEW DEVICE and select Existing Hard Disk. 
 - In the Existing Hard Disk wizard select the rhel image file and then create the instance.
 - Use the instance name to clone rhel machine by updating the `MachineDeployment` field `.spec.template.spec.providerSpec.value.cloudProviderSpec.templateVMName`.