[fix] Fix compilation error that occurs when USE_LOG4CXX is ON

[massakam]

Motivation

When I tried to compile with the USE_LOG4CXX option ON, it failed with the following error:

/pulsar-client-cpp/lib/Log4cxxLogger.cc: In static member function 'static log4cxx::LevelPtr pulsar::Log4CxxLogger::getLevel(pulsar::Logger::Level)':
/pulsar-client-cpp/lib/Log4cxxLogger.cc:63:5: error: control reaches end of non-void function [-Werror=return-type]
     }
     ^

The reason seems to be that there is no default branch in the switch statement in Log4CxxLogger::getLevel, and control may reach the end of the function without returning anything.

pulsar-client-cpp/lib/Log4cxxLogger.cc

Lines 52 to 63 in 872f8ab

	static log4cxx::LevelPtr getLevel(Level level) {
	switch (level) {
	case LEVEL_DEBUG:
	return log4cxx::Level::getDebug();
	case LEVEL_INFO:
	return log4cxx::Level::getInfo();
	case LEVEL_WARN:
	return log4cxx::Level::getWarn();
	case LEVEL_ERROR:
	return log4cxx::Level::getError();
	}
	}

Modifications

Added the default branch to the switch statement. This branch returns INFO.

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