Expose PGPU.resident_VGPUs param on CLI

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Expose VGPU.resident_on param on CLI

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Merge pull request #1420 from simonjbeaumont/resident-vgpus-cli

Expose PGPU.resident_VGPUs param on CLI
Fix a pattern match

It's only by chance that this pattern match worked as intended.

Signed-off-by: John Else <john.else@citrix.com>
CP-5842: Blank VGPU.resident_on on VM shutdown

Signed-off-by: John Else <john.else@citrix.com>
Update API error message

Signed-off-by: John Else <john.else@citrix.com>
CP-5910: Implement Xapi_pgpu.assert_can_run_VGPU and supporting functions

Signed-off-by: John Else <john.else@citrix.com>
CP-5910: Move some code to xapi_pgpu_helpers.ml

Signed-off-by: John Else <john.else@citrix.com>
CP-5910: Update comments in xapi_pgpu_helpers.mli

Signed-off-by: John Else <john.else@citrix.com>
CP-5910: Variable rename for consistency

Signed-off-by: John Else <john.else@citrix.com>