fconf: Add dynamic config DTBs info as property

This patch introduces a better separation between the trusted-boot
related properties, and the dynamic configuration DTBs loading
information.

The dynamic configuration DTBs properties are moved to a new node:
`dtb-registry`. All the sub-nodes present will be provided to the
dynamic config framework to be loaded. The node currently only contains
the already defined configuration DTBs, but can be extended for future
features if necessary.
The dynamic config framework is modified to use the abstraction provided
by the fconf framework, instead of directly accessing the DTBs.

The trusted-boot properties are kept under the "arm,tb_fw" compatible
string, but in a separate `tb_fw-config` node.
The `tb_fw-config` property of the `dtb-registry` node simply points
to the load address of `fw_config`, as the `tb_fw-config` is currently
part of the same DTB.

Change-Id: Iceb6c4c2cb92b692b6e28dbdc9fb060f1c46de82
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
diff --git a/include/plat/arm/common/arm_dyn_cfg_helpers.h b/include/plat/arm/common/arm_dyn_cfg_helpers.h
index 3ad6d54..9fb3131 100644
--- a/include/plat/arm/common/arm_dyn_cfg_helpers.h
+++ b/include/plat/arm/common/arm_dyn_cfg_helpers.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -10,8 +10,6 @@
 #include <stdint.h>
 
 /* Function declarations */
-int arm_dyn_get_config_load_info(void *dtb, int node, unsigned int config_id,
-		uint64_t *config_addr, uint32_t *config_size);
 int arm_dyn_tb_fw_cfg_init(void *dtb, int *node);
 int arm_dyn_get_disable_auth(void *dtb, int node, uint32_t *disable_auth);
 int arm_get_dtb_mbedtls_heap_info(void *dtb, void **heap_addr,