Add provision for flush callback in scheduler message such that
during driver unload scheduler can invoke the flush callback and
components can release the common object ref count which is taken
before posting the message.
Change-Id: I28490e18247239af27feef3a4b53e5080ab012fc
CRs-Fixed: 2034772
Driver is missing couple of deregister handler while bringing down the
scheduler.
Change-Id: I99fe6e9a5d3cac800154945e41e707ebb7ee6396
CRs-Fixed: 2001133
Legacy protocol engine already has a module name 'sch' rename
control path scheduler from sch to scheduler to avoid naming
conflict with protocol sch.
Change-Id: I94ce9aa5037aa75319aaad2287116462444c03f4
CRs-Fixed: 1105115
