plat/arm: Update the fw_config load call and populate it's information

Modified the code to do below changes:

1. Migrates the Arm platforms to the API changes introduced in the
   previous patches by fixing the fconf_load_config() call.
2. Retrieve dynamically the address of tb_fw_config using fconf
   getter api which is subsequently used to write mbedTLS heap
   address and BL2 hash data in the tb_fw_config DTB.

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
Change-Id: I3c9d9345dcbfb99127c61d5589b4aa1532fbf4be
diff --git a/plat/arm/common/arm_bl1_setup.c b/plat/arm/common/arm_bl1_setup.c
index c2f49c2..4011dc9 100644
--- a/plat/arm/common/arm_bl1_setup.c
+++ b/plat/arm/common/arm_bl1_setup.c
@@ -145,8 +145,8 @@
 	/* Initialise the IO layer and register platform IO devices */
 	plat_arm_io_setup();
 
-	/* Load fw config */
-	fconf_load_config();
+	/* Fill the properties struct with the info from the config dtb */
+	fconf_load_config(FW_CONFIG_ID);
 
 #if TRUSTED_BOARD_BOOT
 	/* Share the Mbed TLS heap info with other images */