Const-ify Event::getHeader()'s param

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@15758 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/include/switch_cpp.h

@@ -154,7 +154,7 @@ SWITCH_DECLARE(void) consoleCleanLog(char *msg);
 		 virtual SWITCH_DECLARE_CONSTRUCTOR ~ Event();
 		 SWITCH_DECLARE(const char *) serialize(const char *format = NULL);
 		 SWITCH_DECLARE(bool) setPriority(switch_priority_t priority = SWITCH_PRIORITY_NORMAL);
-		 SWITCH_DECLARE(const char *) getHeader(char *header_name);
+		 SWITCH_DECLARE(const char *) getHeader(const char *header_name);
 		 SWITCH_DECLARE(char *) getBody(void);
 		 SWITCH_DECLARE(const char *) getType(void);
 		 SWITCH_DECLARE(bool) addBody(const char *value);

src/switch_cpp.cpp

@@ -341,7 +341,7 @@ SWITCH_DECLARE(bool) Event::setPriority(switch_priority_t priority)
 	return false;
 }
 
-SWITCH_DECLARE(const char *)Event::getHeader(char *header_name)
+SWITCH_DECLARE(const char *)Event::getHeader(const char *header_name)
 {
 	this_check("");