Merge branch 'mellanox' into 'master'

Update mellanox driver version to 4.7

See merge request hpc-team/ansible_cluster_in_a_box!294

Former-commit-id: f00b9f3c

roles/mellanox_drivers/vars/mellanoxVars.yml

 ---
  #note. do not add '.tgz' to driver src. done in playbook
 #MELLANOX_DRIVER_SRC: "{% if ansible_os_family == 'RedHat'  %}MLNX_OFED_LINUX-4.4-1.0.0.0-rhel7.4-x86_64{% elif ansible_os_family == 'Debian' %}MLNX_OFED_LINUX-3.1-1.0.3-ubuntu14.04-x86_64{% endif %}"
-MELLANOX_DRIVER_SRC: "{% if ansible_os_family == 'RedHat'  %}MLNX_OFED_LINUX-4.5-1.0.1.0-rhel7.6-x86_64{% elif ansible_os_family == 'Debian' %}MLNX_OFED_LINUX-3.1-1.0.3-ubuntu14.04-x86_64{% endif %}"
+#MELLANOX_DRIVER_SRC: "{% if ansible_os_family == 'RedHat'  %}MLNX_OFED_LINUX-4.5-1.0.1.0-rhel7.6-x86_64{% elif ansible_os_family == 'Debian' %}MLNX_OFED_LINUX-3.1-1.0.3-ubuntu14.04-x86_64{% endif %}"
+MELLANOX_DRIVER_SRC: "{% if ansible_os_family == 'RedHat'  %}MLNX_OFED_LINUX-4.7-3.2.9.0-rhel7.7-x86_64{% elif ansible_os_family == 'Debian' %}MLNX_OFED_LINUX-3.1-1.0.3-ubuntu14.04-x86_64{% endif %}"