[ARM] 2930/1: optimized sha1 implementation for ARM

[ARM] 2930/1: optimized sha1 implementation for ARM

Patch from Nicolas Pitre

Here's an ARM assembly SHA1 implementation to replace the default C
version. It is approximately 50% faster than the generic C version. On
an XScale processor running at 400MHz:
	generic C version:	9.8 MB/s
	my version:		14.5 MB/s
This code is useful to quite a few callers in the tree:
crypto/sha1.c:		sha_transform(sctx->state, sctx->buffer, temp);
crypto/sha1.c:			sha_transform(sctx->state, &data[i], temp);
drivers/char/random.c:		sha_transform(buf, (__u8 *)r->pool+i, buf + 5);
drivers/char/random.c:	sha_transform(buf, (__u8 *)data, buf + 5);
net/ipv4/syncookies.c:	sha_transform(tmp + 16, (__u8 *)tmp, tmp + 16 + 5);

Signed-off-by: Nicolas Pitre <nico@cam.org>
Seems to work fine on big-endian as well.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>