regmap: cache: Add 64-bit mode support

Since the mmio has support the 64-bit has been supported for the
64-bit platform, so should the regcache core too.

Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 3cb8c59..1c0210a 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -551,6 +551,14 @@
 		cache[idx] = val;
 		break;
 	}
+#ifdef CONFIG_64BIT
+	case 8: {
+		u64 *cache = base;
+
+		cache[idx] = val;
+		break;
+	}
+#endif
 	default:
 		BUG();
 	}
@@ -584,6 +592,13 @@
 
 		return cache[idx];
 	}
+#ifdef CONFIG_64BIT
+	case 8: {
+		const u64 *cache = base;
+
+		return cache[idx];
+	}
+#endif
 	default:
 		BUG();
 	}