bus: stm32_firewall: allow check on different firewall controllers

Current implementation restricts the check on the firewall controller
being the bus parent. Change this by using the controller referenced
in each firewall queries.

Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
Link: https://lore.kernel.org/r/20260226-debug_bus-v6-4-5d794697798d@foss.st.com
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>

Author: GseoC

drivers/bus/stm32_firewall.c

@@ -267,7 +267,7 @@ int stm32_firewall_populate_bus(struct stm32_firewall_controller *firewall_contr
 		}
 
 		for (i = 0; i < len; i++) {
-			if (firewall_controller->grant_access(firewall_controller,
+			if (firewall_controller->grant_access(firewalls[i].firewall_ctrl,
 							      firewalls[i].firewall_id)) {
 				/*
 				 * Peripheral access not allowed or not defined.