Always map SDL_SCANCODE_GRAVE to the console key.

Currently, the only way to invoke the console which is both platform and
layout independent is to use Shift+Escape.

This change makes sure the ~/`/² key always works as a console key, in
every configuration by matching against its scan code (ie physical
location)

code/sdl/sdl_input.c

@@ -287,7 +287,7 @@ static keyNum_t IN_TranslateSDLToQ3Key( SDL_Keysym *keysym, qboolean down )
 	if( in_keyboardDebug->integer )
 		IN_PrintKey( keysym, key, down );
 
-	if( IN_IsConsoleKey( key, 0 ) )
+	if( keysym->scancode == SDL_SCANCODE_GRAVE || IN_IsConsoleKey( key, 0 ) )
 	{
 		// Console keys can't be bound or generate characters
 		key = K_CONSOLE;