net/bnxt: support GRE flows

net/bnxt: support GRE flows

This patch does the following to support GRE flows:
1. RTE_FLOW_ITEM_TYPE_ANY & RTE_FLOW_ITEM_TYPE_GRE processing
2. Calculate the absolute function ID from the logical VF ID
   passed as part of RTE_FLOW_ACTION_TYPE_VF action.
3. Move bnxt_get_bp API to bnxt_ethdev.c

Signed-off-by: Venkat Duvvuru <venkatkumar.duvvuru@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>