hv:refine vm & vcpu lock

-- move vm_state_lock to other place in vm structure
   to avoid the memory waste because of the page-aligned.
-- remove the memset from create_vm
-- explicitly set max_emul_mmio_regions and vcpuid_entry_nr to 0
   inside create_vm to avoid use without initialization.
-- rename max_emul_mmio_regions to nr_emul_mmio_regions
v1->v2:
   add deinit_emul_io in shutdown_vm

Tracked-On: #4958
Signed-off-by: Mingqiang Chi <mingqiang.chi@intel.com>
Reviewed-by: Grandhi, Sainath <sainath.grandhi@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

hypervisor/include/dm/io_req.h

@@ -286,7 +286,7 @@ void register_mmio_emulation_handler(struct acrn_vm *vm,
  */
 void unregister_mmio_emulation_handler(struct acrn_vm *vm,
 					uint64_t start, uint64_t end);
-
+void deinit_emul_io(struct acrn_vm *vm);
 /**
  * @}
  */