Miscellaneous PSCI code cleanups

This patch implements the following cleanups in PSCI generic code:

1. It reworks the affinity level specific handlers in the PSCI implementation
   such that.

   a. Usage of the 'rc' local variable is restricted to only where it is
      absolutely needed

   b. 'plat_state' local variable is defined only when a direct invocation of
      plat_get_phys_state() does not suffice.

   c. If a platform handler is not registered then the level specific handler
      returns early.

2. It limits the use of the mpidr_aff_map_nodes_t typedef to declaration of
   arrays of the type instead of using it in function prototypes as well.

3. It removes dangling declarations of __psci_cpu_off() and
   __psci_cpu_suspend(). The definitions of these functions were removed in
   earlier patches.

Change-Id: I51e851967c148be9c2eeda3a3c41878f7b4d6978
diff --git a/services/std_svc/psci/psci_setup.c b/services/std_svc/psci/psci_setup.c
index b49b6e8..a5ae4ef 100644
--- a/services/std_svc/psci/psci_setup.c
+++ b/services/std_svc/psci/psci_setup.c
@@ -116,7 +116,7 @@
 int psci_get_aff_map_nodes(unsigned long mpidr,
 			   int start_afflvl,
 			   int end_afflvl,
-			   mpidr_aff_map_nodes_t mpidr_nodes)
+			   aff_map_node_t *mpidr_nodes[])
 {
 	int rc = PSCI_E_INVALID_PARAMS, level;
 	aff_map_node_t *node;