mlnx-en-2.2-1.0.1 is not ofed but ordinary driver (mlx4_en) that works with kernel tcp/ip stack.
install.sh is the script that compiles and installs this driver. Not latest version of it should have been included in your CentOS 6.5 already.
Look for appropriate ofed here: Mellanox Products: Mellanox OpenFabrics Enterprise Distribution for Linux (MLNX_OFED)
Unfortunatly i can't help with those conflicts of yours.