psci: Fix the function type for psci_initcall_t

Functions called through a psci_initcall_t pointer all have
non-const arguments. Fix the type definition to avoid tripping
indirect call checks with CFI_CLANG.
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220908215504.3686827-9-samitolvanen@google.com

drivers/firmware/psci/psci.c

@@ -274,7 +274,7 @@ static void set_conduit(enum arm_smccc_conduit conduit)
 	psci_conduit = conduit;
 }
 
-static int get_set_conduit_method(struct device_node *np)
+static int get_set_conduit_method(const struct device_node *np)
 {
 	const char *method;
 
@@ -528,7 +528,7 @@ typedef int (*psci_initcall_t)(const struct device_node *);
  *
  * Probe based on PSCI PSCI_VERSION function
  */
-static int __init psci_0_2_init(struct device_node *np)
+static int __init psci_0_2_init(const struct device_node *np)
 {
 	int err;
 
@@ -549,7 +549,7 @@ static int __init psci_0_2_init(struct device_node *np)
 /*
  * PSCI < v0.2 get PSCI Function IDs via DT.
  */
-static int __init psci_0_1_init(struct device_node *np)
+static int __init psci_0_1_init(const struct device_node *np)
 {
 	u32 id;
 	int err;
@@ -585,7 +585,7 @@ static int __init psci_0_1_init(struct device_node *np)
 	return 0;
 }
 
-static int __init psci_1_0_init(struct device_node *np)
+static int __init psci_1_0_init(const struct device_node *np)
 {
 	int err;