Partial revert of r330873 ('[Driver] Reland "Android triples are not
aliases for other triples."')
While we don't want `-target aarch64-linux-android` to alias to non
*-android libs and binaries, it turns out we do want the opposite. Ie. We
would like for `-target aarch64-linux-gnu` to still be able to use
*-android libs and binaries.
In fact, this is used to cross assemble and link the Linux kernel for
`-target aarch64-linux-gnu` needs to be used for the Linux kernel when
using the android binutils prebuilts.
The use of `-target aarch64-linux-android` on C source files will cause
Clang to perform optimizations based on the presence of bionic (due to
r265481 ('Faster stack-protector for Android/AArch64.')) which is
invalid within the Linux kernel and will produce a non-bootable kernel
Of course, you could just use the standard binutils (aarch64-linux-gnu),
but Android does not distribute these. So this patch fixes a problem
that only occurs when cross assembling and linking a Linux kernel with
the Android provided binutils, which is what is done within Android's
hermetic build system.