Add gpfs volume driver configuration flags

Add support for gpfs volume driver configuration flags.  Add
initialization of gpfs_mount_point_base directory with proper
owner and permission settings.

Use Havana location of gpfs driver.  In Icehouse, this will
be updated to reflect change in driver path under "ibm" subdirectory.

Partially implements: blueprint gpfs-storage-support
Change-Id: I002fc73c1d1fa89d8cb56d8da048426701251a46
Merge "Add gpfs volume driver configuration flags"