refactor(rpi): move more platform-specific code into common

In preparation for RPi 5 support, which will reuse most of the RPi 4
logic except for DTB patching.

Change-Id: I6f6ef96933711a1798757a3389adae1b8ee3de6c
Signed-off-by: Mario Bălănică <mariobalanica02@gmail.com>
diff --git a/plat/rpi/common/include/rpi_shared.h b/plat/rpi/common/include/rpi_shared.h
index ddf239e..1b6c426 100644
--- a/plat/rpi/common/include/rpi_shared.h
+++ b/plat/rpi/common/include/rpi_shared.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2024, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -23,6 +23,8 @@
 #endif
 			    );
 
+uintptr_t rpi4_get_dtb_address(void);
+
 /* Optional functions required in the Raspberry Pi 3 port */
 unsigned int plat_rpi3_calc_core_pos(u_register_t mpidr);
 
@@ -38,4 +40,10 @@
 
 int plat_rpi_get_model(void);
 
+/*******************************************************************************
+ * Platform implemented functions
+ ******************************************************************************/
+
+void plat_rpi_bl31_custom_setup(void);
+
 #endif /* RPI3_PRIVATE_H */