bus: firewall: move stm32_firewall header file in include folder

Other driver than RIFSC and ETZPC can implement firewall ops, such as
RCC.
In order for them to have access to the ops and type of this framework,
we need to get the `stm32_firewall.h` file in the include/ folder.

Signed-off-by: Clément Le Goffic <clement.legoffic@foss.st.com>
Signed-off-by: Clément Le Goffic <legoffic.clement@gmail.com>
Acked-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
Link: https://lore.kernel.org/r/20260210-b4-firewall-upstream-v8-1-097c1e47af82@gmail.com
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>

drivers/bus/stm32_etzpc.c

@@ -5,6 +5,7 @@
 
 #include <linux/bitfield.h>
 #include <linux/bits.h>
+#include <linux/bus/stm32_firewall.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/init.h>
@@ -16,8 +17,6 @@
 #include <linux/platform_device.h>
 #include <linux/types.h>
 
-#include "stm32_firewall.h"
-
 /*
  * ETZPC registers
  */

drivers/bus/stm32_firewall.c

@@ -5,6 +5,7 @@
 
 #include <linux/bitfield.h>
 #include <linux/bits.h>
+#include <linux/bus/stm32_firewall.h>
 #include <linux/bus/stm32_firewall_device.h>
 #include <linux/device.h>
 #include <linux/err.h>
@@ -18,8 +19,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 
-#include "stm32_firewall.h"
-
 /* Corresponds to STM32_FIREWALL_MAX_EXTRA_ARGS + firewall ID */
 #define STM32_FIREWALL_MAX_ARGS		(STM32_FIREWALL_MAX_EXTRA_ARGS + 1)
 

drivers/bus/stm32_rifsc.c

@@ -5,6 +5,7 @@
 
 #include <linux/bitfield.h>
 #include <linux/bits.h>
+#include <linux/bus/stm32_firewall.h>
 #include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/err.h>
@@ -17,8 +18,6 @@
 #include <linux/platform_device.h>
 #include <linux/types.h>
 
-#include "stm32_firewall.h"
-
 /*
  * RIFSC offset register
  */