pinctrl: sh-pfc: checker: Improve pin function checks

Improve the checks for pin function descriptors:
  1. Merge declaration and assignment of the local variable for the
     current pin function,
  2. Pin function names must be unique.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20200110131927.1029-8-geert+renesas@glider.be

drivers/pinctrl/sh-pfc/core.c

@@ -849,7 +849,6 @@ static void __init sh_pfc_check_cfg_reg(const char *drvname,
 
 static void __init sh_pfc_check_info(const struct sh_pfc_soc_info *info)
 {
-	const struct sh_pfc_function *func;
 	const char *drvname = info->name;
 	unsigned int *refcnts;
 	unsigned int i, j, k;
@@ -890,11 +889,17 @@ static void __init sh_pfc_check_info(const struct sh_pfc_soc_info *info)
 		return;
 
 	for (i = 0; i < info->nr_functions; i++) {
-		func = &info->functions[i];
+		const struct sh_pfc_function *func = &info->functions[i];
+
 		if (!func->name) {
 			sh_pfc_err("empty function %u\n", i);
 			continue;
 		}
+		for (j = 0; j < i; j++) {
+			if (same_name(func->name, info->functions[j].name))
+				sh_pfc_err("function %s: name conflict\n",
+					   func->name);
+		}
 		for (j = 0; j < func->nr_groups; j++) {
 			for (k = 0; k < info->nr_groups; k++) {
 				if (same_name(func->groups[j],