refactor(st): move boot backup register management

This backup register used to pass boot information to BL33, has the
same mapping for ST platforms. Its management can then be moved to
common directory.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: Ic873f099c1f87c6ba2825b4946365ae6a9687798
diff --git a/plat/st/stm32mp1/bl2_plat_setup.c b/plat/st/stm32mp1/bl2_plat_setup.c
index 87d2d39..eeabd09 100644
--- a/plat/st/stm32mp1/bl2_plat_setup.c
+++ b/plat/st/stm32mp1/bl2_plat_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2022, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2023, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -290,10 +290,7 @@
 		panic();
 	}
 
-	stm32_save_boot_interface(boot_context->boot_interface_selected,
-				  boot_context->boot_interface_instance);
-	stm32_save_boot_auth(boot_context->auth_status,
-			     boot_context->boot_partition_used_toboot);
+	stm32_save_boot_info(boot_context);
 
 #if STM32MP_USB_PROGRAMMER && STM32MP15
 	/* Deconfigure all UART RX pins configured by ROM code */