Build Android binaries with a larger page size (#12246)

Apparently Google says we should do this. Also apparently Google's
version of the NDK doesn't do this by default. Thread the needle by
manually passing it.

Closes #12220

Author: alexcrichton

ci/build-build-matrix.js

@@ -68,6 +68,10 @@ const array = [
     "build": "aarch64-android",
     "os": ubuntu,
     "target": "aarch64-linux-android",
+    // See https://developer.android.com/guide/practices/page-sizes
+    // for some more commentary, but apparently Google recommends passing this
+    // linker flag.
+    "env": { "RUSTFLAGS": "-Clink-arg=-z -Clink-arg=max-page-size=16384" },
   },
   {
     "build": "x86_64-android",