regmap: Implement support for 32 bit registers and values

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 7e18d1e..69d4c9c 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -372,6 +372,13 @@
 		cache[idx] = val;
 		break;
 	}
+	case 4: {
+		u32 *cache = base;
+		if (cache[idx] == val)
+			return true;
+		cache[idx] = val;
+		break;
+	}
 	default:
 		BUG();
 	}
@@ -393,6 +400,10 @@
 		const u16 *cache = base;
 		return cache[idx];
 	}
+	case 4: {
+		const u32 *cache = base;
+		return cache[idx];
+	}
 	default:
 		BUG();
 	}