Incorrect spelling of currency

The code from ROMessage.h
- (void)writeCurrency:(nullable NSDecimalNumber *)aCurrency withName:(nullable NSString *)aName __attribute__((swift_name("ROSerialization.writeCurrrency(_:withName:)")));

The letter r occurs 3 times in "ROSerialization.writeCurrrency(_:withName:)" and causes compilation errors in Xcode.

Oops. fixing…