ui/cocoa: Remove stray tabs

The ui/cocoa.m file has just three lines with hardcoded tabs; fix them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: 1387886052-27067-1-git-send-email-peter.maydell@linaro.org

ui/cocoa.m

@@ -427,8 +427,8 @@ - (void) switchSurface:(DisplaySurface *)surface
         CGDataProviderRelease(dataProviderRef);
 
     //sync host window color space with guests
-	screen.bitsPerPixel = surface_bits_per_pixel(surface);
-	screen.bitsPerComponent = surface_bytes_per_pixel(surface) * 2;
+    screen.bitsPerPixel = surface_bits_per_pixel(surface);
+    screen.bitsPerComponent = surface_bytes_per_pixel(surface) * 2;
 
     dataProviderRef = CGDataProviderCreateWithData(NULL, surface_data(surface), w * 4 * h, NULL);
 
@@ -774,7 +774,7 @@ - (id) init
         [normalWindow setContentView:cocoaView];
         [normalWindow useOptimizedDrawing:YES];
         [normalWindow makeKeyAndOrderFront:self];
-		[normalWindow center];
+        [normalWindow center];
 
     }
     return self;