Remove auth_signal() function...

and associated dead code
Following a suggestion from @mliszcz

Author: bourtemb

cppapi/server/dserversignal.cpp

@@ -269,15 +269,6 @@ void DServerSignal::register_class_signal(long signo,bool handler,DeviceClass *c
 				        (const char *)"DServerSignal::register_class_signal");
 	}
 
-	if (auth_signal(signo) == false)
-	{
-		TangoSys_OMemStream o;
-		o << "Signal " << sig_name[signo] << "is not authorized with your OS" << std::ends;
-		Except::throw_exception((const char *)API_SignalOutOfRange,
-				        o.str(),
-				        (const char *)"DServerSignal::register_class_signal");
-	}
-
 #ifndef _TG_WINDOWS_
 	if ((auto_signal(signo) == true) && (handler == true))
 	{
@@ -385,15 +376,6 @@ void DServerSignal::register_dev_signal(long signo,bool handler,DeviceImpl *dev_
 				      (const char *)"DServerSignal::register_dev_signal");
 	}
 
-	if (auth_signal(signo) == false)
-	{
-		TangoSys_OMemStream o;
-		o << "Signal " << sig_name[signo] << "is not authorized with your OS" << std::ends;
-		Except::throw_exception((const char *)API_SignalOutOfRange,
-				      o.str(),
-				      (const char *)"DServerSignal::register_dev_signal");
-	}
-
 #ifndef _TG_WINDOWS_
 	if ((auto_signal(signo) == true) && (handler == true))
 	{

cppapi/server/dserversignal.h

@@ -150,14 +150,6 @@ protected :
 	}
 #endif
 
-#if (defined __GLIBC__ || defined __darwin__ || defined __FreeBSD__ || defined __OpenBSD__)
-	static inline bool auth_signal(TANGO_UNUSED(long s)) {return true;}
-#endif
-
-#ifdef _TG_WINDOWS_
-	static inline bool auth_signal(long s) {return true;}
-#endif
-
 	static std::string 			sig_name[_NSIG];
 
 };