JANITORIAL: Fix typos

engines/sword25/gfx/graphicengine.cpp

@@ -362,7 +362,7 @@ void  GraphicEngine::updateLastFrameDuration() {
 }
 
 bool GraphicEngine::saveThumbnailScreenshot(const Common::String &filename) {
-	// Note: In ScumMVM, rather than saivng the thumbnail to a file, we store it in memory
+	// Note: In ScummVM, rather than saving the thumbnail to a file, we store it in memory
 	// until needed when creating savegame files
 	delete _thumbnail;