staging: fsl-mc: Refactored fsl_mc_object_allocator driver init/exit

 The fsl_mc_allocator driver does not need to be its own module
 as it is tightly integrated into the MC bus main driver. It is really
 just a sub-component of the MC bus driver. By not making fsl_mc_allocator
 its own module, we can have more control of when its initialization happens
 and we want it to happen before any driver that depends on the MC bus
 driver gets initialized.

Signed-off-by: J. German Rivera <German.Rivera@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>