Add boot_command support

[tuxtof]

/kind feature

Describe the solution you'd like

implement boot_command support as we can find in some other provider

Anything else you would like to add:

boot_command functionality is not possible today as there is no API to have access to the console for sending keystrokes.

As this is a limitation of AOS we cannot provide any solution yet. Please feel free to file a feature request at Nutanix Support and link to this issue.