At present, `log-file` location of glusterfs client mount is decided
by the plugin, however at times, users/admin want to configure log-file
of gluster fuse client process on their own in some setups. Even though they can pass log-file
mount option through storage class, before this patch glusterfs plugin
always discard it. This patch enable/give preference
to admin supplied log-file mount option if specified in storage class.
If the log-file mount option is incomplete or wrong, plugin fallback to the
location which is carved out by the combination of pvc and pod name.
Signed-off-by: Humble Chirammal <hchiramm@redhat.com>