This reverts the non-ARM portions of 97999919bb.
x86_64 perlasm already makes .globl imply .hidden. (Confusingly, ARM does not.)
Since we don't need it, revert those to minimize divergence with upstream.

Change-Id: I2d205cfb1183e65d4f18a62bde187d206b1a96de
Reviewed-on: https://boringssl-review.googlesource.com/3610
Reviewed-by: Adam Langley <agl@google.com>

We are leaking asm symbols in Android builds because the asm code isn't
affected by -fvisibility=hidden. This change hides all asm symbols.

This assumes that no asm symbols are public API and that should be true.
Some points to note:

In crypto/rc4/asm/rc4-md5-x86_64.pl there are |RC4_set_key| and
|RC4_options| functions which aren't getting marked as hidden. That's
because those functions aren't actually ever generated. (I'm just trying
to minimise drift with upstream here.)

In crypto/rc4/asm/rc4-x86_64.pl there's |RC4_options| which is "public"
API, except that we've never had it in the header files. So I've just
deleted it. Since we have an internal caller, we'll probably have to put
it back in the future, but it can just be done in rc4.c to save
problems.

BUG=448386

Change-Id: I3846617a0e3d73ec9e5ec3638a53364adbbc6260
Reviewed-on: https://boringssl-review.googlesource.com/3520
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>

This is an initial cut at aarch64 support. I have only qemu to test it
however—hopefully hardware will be coming soon.

This also affects 32-bit ARM in that aarch64 chips can run 32-bit code
and we would like to be able to take advantage of the crypto operations
even in 32-bit mode. AES and GHASH should Just Work in this case: the
-armx.pl files can be built for either 32- or 64-bit mode based on the
flavour argument given to the Perl script.

SHA-1 and SHA-256 don't work like this however because they've never
support for multiple implementations, thus BoringSSL built for 32-bit
won't use the SHA instructions on an aarch64 chip.

No dedicated ChaCha20 or Poly1305 support yet.

Change-Id: Ib275bc4894a365c8ec7c42f4e91af6dba3bd686c
Reviewed-on: https://boringssl-review.googlesource.com/2801
Reviewed-by: Adam Langley <agl@google.com>