Remove the env var for doca driver

[surajssd]

This temporary fix is not needed any more as the new release already ships with this:

aks-rdma-infiniband/configs/nicclusterpolicy/base/nic.yaml

Lines 25 to 29 in 449020a

	env:
	# TODO: Temporary fix to avoid race condition where the kernel module fails to load.
	# Refer: https://github.com/Mellanox/doca-driver-build/issues/52
	- name: OFED_BLACKLIST_MODULES_FILE
	value: "/host/etc/modprobe.d/blacklist-ofed-modules.conf"

new code in doca driver build:
https://github.com/Mellanox/doca-driver-build/blob/15b9d187ae43511c0632eb5a5fb538155bc6a297/entrypoint.sh#L50