refactor(ff-a): replace `plat_ffa_` prefix for public functions

Replace `plat_ffa_` prefix with `ffa_{file_name}_` prefix. Only do so
for public functions to avoid unnecessary churn (private functions are
renamed in the next commit).

Change-Id: I847c218f134a2519a45a3af1d6c4b953db9c1cbb
Signed-off-by: Karl Meakin <karl.meakin@arm.com>
diff --git a/src/init.c b/src/init.c
index e4362bf..ddd90d5 100644
--- a/src/init.c
+++ b/src/init.c
@@ -47,7 +47,7 @@
 	/* Make sure the console is initialised before calling dlog. */
 	plat_console_init();
 
-	plat_ffa_log_init();
+	ffa_init_log();
 
 	mpool_init(&ppool, MM_PPOOL_ENTRY_SIZE);
 	mpool_add_chunk(&ppool, ptable_buf, sizeof(ptable_buf));
@@ -150,7 +150,7 @@
 		      manifest_strerror(manifest_ret));
 	}
 
-	plat_ffa_set_tee_enabled(manifest->ffa_tee_enabled);
+	ffa_init_set_tee_enabled(manifest->ffa_tee_enabled);
 
 	if (!plat_iommu_init(&fdt, mm_stage1_locked, &ppool)) {
 		panic("Could not initialize IOMMUs.");
@@ -191,7 +191,7 @@
 	mm_vm_enable_invalidation();
 
 	/* Perform platform specfic FF-A initialization. */
-	plat_ffa_init(&ppool);
+	ffa_init(&ppool);
 
 	/* Initialise the API page pool. ppool will be empty from now on. */
 	api_init(&ppool);