RDMA/irdma: Add GEN3 core driver support

RDMA/irdma: Add GEN3 core driver support

Introduce support for the GEN3 auxiliary core driver, which is
responsible for initializing PCI-level RDMA resources.

Facilitate host-driver communication with the device's Control Plane (CP)
to discover capabilities and perform privileged operations through an
RDMA-specific messaging interface built atop the IDPF mailbox and virtual
channel protocol.

Establish the RDMA virtual channel message interface and incorporate
operations to retrieve the hardware version and discover capabilities
from the CP.

Additionally, set up the RDMA MMIO regions and initialize the RF structure.

Signed-off-by: Mustafa Ismail <mustafa.ismail@intel.com>
Co-developed-by: Tatyana Nikolova <tatyana.e.nikolova@intel.com>
Signed-off-by: Tatyana Nikolova <tatyana.e.nikolova@intel.com>
Link: https://patch.msgid.link/20250827152545.2056-3-tatyana.e.nikolova@intel.com
Tested-by: Jacob Moroni <jmoroni@google.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>