feat: helper to reset and free partition notification bindings

The helper utility `vm_reset_notifications` added in this patch is
needed when partition manager reclaims resources from an aborted
partition.

The `ffa_vm_free_resources` function is extended to accept a new
parameter that tracks the associated memory page pool. This facilitates
any memory released by partition manager to be reallocated to the said
page pool.

Moreover, the function `ffa_vm_destroy` has been renamed to
`ffa_vm_nwd_free` for better clarity. And, the function
`ffa_vm_nwd_create` has been renamed to `ffa_vm_nwd_alloc`.

Change-Id: I868bef6bdbbde468f2bf2ce5597a55c6ae95d777
Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
diff --git a/inc/hf/api.h b/inc/hf/api.h
index cd71886..f923efb 100644
--- a/inc/hf/api.h
+++ b/inc/hf/api.h
@@ -22,6 +22,7 @@
 }
 
 void api_init(struct mpool *ppool);
+struct mpool *api_get_ppool(void);
 struct vcpu *api_ffa_get_vm_vcpu(struct vm *vm, struct vcpu *current);
 void api_regs_state_saved(struct vcpu *vcpu);
 int64_t api_mailbox_writable_get(const struct vcpu *current);