net/bnxt: modify VF representor allocation sequence

net/bnxt: modify VF representor allocation sequence

When the VF representor interface is created, the VF pair relationship
is established between the VF and it is representor. If the pair
already exists then the pair needs to be deleted before allocation.
This could happen if the application is abruptly killed and restarted.
If the deletion of an existing VF rep is not done then hw pipeline is
not cleaned and a new allocation shall leave the hw in inconsistent
state.

Signed-off-by: Kishore Padmanabha <kishore.padmanabha@broadcom.com>
Signed-off-by: Venkat Duvvuru <venkatkumar.duvvuru@broadcom.com>
Reviewed-by: Shahaji Bhosle <sbhosle@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>