net/bnxt: fix RSS context cleanup

net/bnxt: fix RSS context cleanup

The PMD is allocating an extra RSS context with each port start.
But it is freeing only one RSS context during port stop. So at some point
we run out of RSS contexts when we do multiple port stop/start sequences.
bnxt_hwrm_vnic_ctx_alloc() is called by bnxt_setup_one_vnic(), but
bnxt_hwrm_vnic_ctx_free() is not called in the corresponding
bnxt_free_one_vnic().

Fix this by calling bnxt_hwrm_vnic_ctx_free() in bnxt_free_one_vnic().

Fixes: 7fe5668d2ea3 ("net/bnxt: support VLAN filter and strip")
Cc: stable@dpdk.org
Signed-off-by: Ajit Khaparde <ajit.khaparde@broadcom.com>