idpf: add core init and interrupt request

As the mailbox is setup, add the necessary send and receive
mailbox message framework to support the virtchnl communication
between the driver and device Control Plane (CP).

Add the core initialization. To start with, driver confirms the
virtchnl version with the CP. Once that is done, it requests
and gets the required capabilities and resources needed such as
max vectors, queues etc.

Based on the vector information received in 'VIRTCHNL2_OP_GET_CAPS',
request the stack to allocate the required vectors. Finally add
the interrupt handling mechanism for the mailbox queue and enable
the interrupt.

Note: Checkpatch issues a warning about IDPF_FOREACH_VPORT_VC_STATE and
IDPF_GEN_STRING being complex macros and should be enclosed in parentheses
but it's not the case. They are never used as a statement and instead only
used to define the enum and array.

Co-developed-by: Alan Brady <alan.brady@intel.com>
Signed-off-by: Alan Brady <alan.brady@intel.com>
Co-developed-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Co-developed-by: Joshua Hay <joshua.a.hay@intel.com>
Signed-off-by: Joshua Hay <joshua.a.hay@intel.com>
Co-developed-by: Madhu Chittim <madhu.chittim@intel.com>
Signed-off-by: Madhu Chittim <madhu.chittim@intel.com>
Co-developed-by: Phani Burra <phani.r.burra@intel.com>
Signed-off-by: Phani Burra <phani.r.burra@intel.com>
Co-developed-by: Shailendra Bhatnagar <shailendra.bhatnagar@intel.com>
Signed-off-by: Shailendra Bhatnagar <shailendra.bhatnagar@intel.com>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>