Added the build instructions for optimization

Building-For-Linux.md

@@ -51,6 +51,15 @@ sudo make install (currently doesn't work, needs to be fixed)
 ```
 Optionally, you can use "cmake -i .." to adjust various options (e.g. disable the Qt GUI).
 
+### Building Citra (Optimized):
+
+```
+mkdir build && cd build
+cmake .. -DCMAKE_BUILD_TYPE=Release
+make
+sudo make install (currently doesn't work, needs to be fixed)
+```
+
 ### Building with debug symbols:
 
 ```