VEP 97.1 hypervisor feature discovery (#122)

* hypervisor feature discovery

Signed-off-by: Vy Ta <vyta@microsoft.com>

* update vep number

Signed-off-by: Vy Ta <vyta@microsoft.com>

* Apply suggestions from code review

Co-authored-by: Jed Lejosne <jean-edouard@users.noreply.github.com>
Signed-off-by: vyta <vvyy.ta@outlook.com>

* update based on feedback

Signed-off-by: Vy Ta <vyta@microsoft.com>

* Rephrasing changes

Signed-off-by: Harshit Gupta <guptaharshit@microsoft.com>

* Add examples from PoC and kubevirt-capability-check binary

Signed-off-by: Harshit Gupta <guptaharshit@microsoft.com>

* Add RegisterCapability fn and simplify Cap Support Regn

Introduce RegisterCapability function to allow platforms to register custom capabilities.
Replace builder pattern code with simple function calls to elucidate the design.

Signed-off-by: Harshit Gupta <guptaharshit@microsoft.com>

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Signed-off-by: Vy Ta <vyta@microsoft.com>
Signed-off-by: vyta <vvyy.ta@outlook.com>
Signed-off-by: Harshit Gupta <guptaharshit@microsoft.com>
Co-authored-by: Jed Lejosne <jean-edouard@users.noreply.github.com>
Co-authored-by: Harshit Gupta <guptaharshit@microsoft.com>

Author: 3 people