(experimental) Enable VirGL if the flag file exists

If `/sdcard/linux/virglrenderer` exists, it overrides GPU config with
VirGL

Bug: 380366206
Test: create /sdcard/linux/virglrenderer and check crosvm params
Change-Id: I3e4907d2b5f98b8f6309894509334a0d61562b0e
diff --git a/android/TerminalApp/res/values/strings.xml b/android/TerminalApp/res/values/strings.xml
index 851eaab..da8ca84 100644
--- a/android/TerminalApp/res/values/strings.xml
+++ b/android/TerminalApp/res/values/strings.xml
@@ -132,4 +132,7 @@
     <string name="service_notification_content">Click to open the terminal</string>
     <!-- Notification action button for closing the virtual machine [CHAR LIMIT=20] -->
     <string name="service_notification_quit_action">Close</string>
+
+    <!-- VirGL is the name of hardware acceleration for VM, the name is supposed not to be translated. [CHAR LIMIT=20] -->
+    <string name="virgl_enabled">VirGL is enabled</string>
 </resources>