net/bnxt: cleanup and check ULP context allocation

net/bnxt: cleanup and check ULP context allocation

Set ulp_ctx explicitly to NULL in ulp_ctx_deinit() so that representor
init is aborted if parent ulp context is not initialized.
Also check for the same before creation of port default rules.
Additional checks added in VF rep dev ops for proper parent dev
initialization, to avoid null pointer dereference.

Fixes: 322bd6e70272 ("net/bnxt: add port representor infrastructure")
Fixes: 313ac35ac701 ("net/bnxt: support ULP session manager init")
Cc: stable@dpdk.org
Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Venkat Duvvuru <venkatkumar.duvvuru@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>