macosx: fixed potential crashes when localizing strings

(cherry picked from commit fb5766e398fa651791f5b7b7071a04ec175d9e5f)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/gui/macosx/intf.h

@@ -48,7 +48,7 @@ unsigned int CocoaKeyToVLC( unichar i_key );
 
 #define VLCIntf [[VLCMain sharedInstance] intf]
 
-#define _NS(s) [[VLCMain sharedInstance] localizedString: _(s)]
+#define _NS(s) [[VLCMain sharedInstance] localizedString: s]
 /* Get an alternate version of the string.
  * This string is stored as '1:string' but when displayed it only displays
  * the translated string. the translation should be '1:translatedstring' though */

modules/gui/macosx/intf.m

@@ -1000,7 +1000,7 @@ static VLCMain *_o_sharedMainInstance = nil;
 
     if( psz != NULL )
     {
-        o_str = [NSString stringWithCString: psz encoding:NSUTF8StringEncoding];
+        o_str = [NSString stringWithCString: _(psz) encoding:NSUTF8StringEncoding];
 
         if( o_str == NULL )
         {