Adding two Exported APIs in DLL - GmmInit and GmmDestroy.
GmmInit initializes singleton global context and ClientContext.
This avoid the need for clients to fill up function table.
Change-Id: I3bab29d2c10fd4d06cf78e1f33c9479d536477da
Signed-off-by: drprajap <dimpalben.r.prajapati@intel.com>