Remove commented-out cpp_std.

(It shows up in codesearch when trying to burn down the remaining projects not moved to C++20, despite this project actually already being on C++20.)

Change-Id: Ic0265b088fdd3e695d72a0d829dbcfe5b9069e72
diff --git a/Android.bp b/Android.bp
index 7d4af1c..cef5082 100644
--- a/Android.bp
+++ b/Android.bp
@@ -68,8 +68,6 @@
     header_libs: [
         "libopenscreen_absl_headers",
     ],
-
-//    cpp_std: "c++17",
 }
 
 osp_discovery_srcs = [