Move device specific PFVF logic related to the PF to the newly created
adf_gen2_pfvf.c.
This refactory is done to isolate the GEN2 PFVF code into its own file
in preparation for the introduction of support for PFVF for GEN4
devices.

In addition the PFVF PF logic for dh895xcc has been isolated to
adf_dh895xcc_hw_data.c.
Signed-off-by: Marco Chiappero <marco.chiappero@intel.com>
Co-developed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>