fix compile issues

mapstructure.go

diff --git a/mapstructure.go b/mapstructure.go
index 143f519..dae28dd 100644
--- a/mapstructure.go
+++ b/mapstructure.go
@@ -558,10 +558,10 @@
 			// doing case-insensitive search.
 			for dataValKey, _ := range dataValKeys {
 				mK, ok := dataValKey.Interface().(string)
-+                               if !ok {
-+                                       // Not a string key
-+                                       continue
-+                               }
+				if !ok {
+					// Not a string key
+					continue
+				}
 
 				if strings.EqualFold(mK, fieldName) {
 					rawMapKey = dataValKey