fix(legacy): fix maximum pin length when upgrading from old storage format

legacy/firmware/config.c

@@ -319,7 +319,7 @@ static secbool config_upgrade_v10(void) {
   storage_unlock(PIN_EMPTY, PIN_EMPTY_LEN, NULL);
   if (config.has_pin) {
     storage_change_pin(PIN_EMPTY, PIN_EMPTY_LEN, (const uint8_t *)config.pin,
-                       strnlen(config.pin, MAX_PIN_LEN), NULL, NULL);
+                       strnlen(config.pin, MAX_OLD_PIN_LEN), NULL, NULL);
   }
 
   while (pin_wait != 0) {

legacy/firmware/config.h

@@ -56,6 +56,8 @@ typedef struct {
   STORAGE_BYTES(public_key, 33);
 } StorageHDNode;
 
+#define MAX_OLD_PIN_LEN 9
+
 typedef struct _Storage {
   uint32_t version;
 
@@ -63,7 +65,7 @@ typedef struct _Storage {
   STORAGE_STRING(mnemonic, 241)
   STORAGE_BOOL(passphrase_protection)
   STORAGE_UINT32(pin_failed_attempts)
-  STORAGE_STRING(pin, 10)
+  STORAGE_STRING(pin, MAX_OLD_PIN_LEN + 1)
   STORAGE_STRING(language, 17)
   STORAGE_STRING(label, 33)
   STORAGE_BOOL(imported)