Merge pull request #83503 from finagolfin/droid
[6.2][build] Make it possible to build a cross-compilation toolchain for Android, including Testing
Add a linker flag for the upcoming 16 KB page support in Android, generate an Android CMake toolchain file that can be used to cross-compile repos like cmark and Testing, and add a build flag that makes it easy to build cross-compilation toolchains, by disabling the cross-compilation of all host tools and macros for listed --cross-compile-hosts, leaving only the Swift runtime libraries in a cross-compilation SDK.
