refactor(st): move GIC code to common directory

The GIC v2 initialization code could be shared to other ST platforms.
The stm32mp1_gic.c file is then moved to common directory, and renamed
stm32mp_gic.c.
The functions are also prefixed with stm32mp_gic.

Change-Id: I60820823b470217d3a95cc569f941c2cb923dfa9
Signed-off-by: Yann Gautier <yann.gautier@st.com>
diff --git a/plat/st/stm32mp1/sp_min/sp_min_setup.c b/plat/st/stm32mp1/sp_min/sp_min_setup.c
index 50b0794..b46f4af 100644
--- a/plat/st/stm32mp1/sp_min/sp_min_setup.c
+++ b/plat/st/stm32mp1/sp_min/sp_min_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
  */
@@ -7,9 +7,8 @@
 #include <assert.h>
 #include <string.h>
 
-#include <platform_def.h>
-
 #include <arch_helpers.h>
+#include <bl32/sp_min/platform_sp_min.h>
 #include <common/bl_common.h>
 #include <common/debug.h>
 #include <context.h>
@@ -27,7 +26,7 @@
 #include <lib/xlat_tables/xlat_tables_v2.h>
 #include <plat/common/platform.h>
 
-#include <platform_sp_min.h>
+#include <platform_def.h>
 
 /******************************************************************************
  * Placeholder variables for copying the arguments that have been passed to
@@ -181,7 +180,7 @@
 {
 	generic_delay_timer_init();
 
-	stm32mp1_gic_init();
+	stm32mp_gic_init();
 
 	if (stm32_iwdg_init() < 0) {
 		panic();