Shader: Initial implementation of x86_x64 JIT compiler for Pica vertex shaders.

- Config: Add an option for selecting to use shader JIT or interpreter.
- Qt: Add a menu option for enabling/disabling the shader JIT.

src/citra_qt/main.ui

@@ -66,6 +66,7 @@
     <addaction name="action_Stop"/>
     <addaction name="separator"/>
     <addaction name="action_Use_Hardware_Renderer"/>
+    <addaction name="action_Use_Shader_JIT"/>
     <addaction name="action_Configure"/>
    </widget>
    <widget class="QMenu" name="menu_View">
@@ -153,6 +154,14 @@
     <string>Use Hardware Renderer</string>
    </property>
   </action>
+  <action name="action_Use_Shader_JIT">
+   <property name="checkable">
+    <bool>true</bool>
+   </property>
+   <property name="text">
+    <string>Use Shader JIT</string>
+   </property>
+  </action>
   <action name="action_Configure">
    <property name="text">
     <string>Configure ...</string>