fix precompiled driver container failures when enabling OpenRM

[tariq1890]

We have found that the OpenRM modules fail to load successfully as it's unable to find the firmware files in the /lib/firmware directory. This was happening due to two reasons:

1. The /lib/firmware files were being installed during the container image build-time. See here
2. The /lib/firmware files were wiped out as we mount the /run/nvidia/driver/lib/firmware directory . See here

To fix this issue, we make the following changes

1. We only download (and not install) the nvidia-driver-${DRIVER_BRANCH}-server package, so that the actual takes place during container runtime and the lib/firmware files are installed AFTER the mount
2. Add logic to point the override firmware file search path in /sys/module/firmware_class/parameters/path. This is performed in non precompiled containers and it is needed for the OpenRM Kernel module to load successfully