crypto: lib/sha1 - fold linux/cryptohash.h into crypto/sha.h

<linux/cryptohash.h> sounds very generic and important, like it's the
header to include if you're doing cryptographic hashing in the kernel.
But actually it only includes the library implementation of the SHA-1
compression function (not even the full SHA-1).  This should basically
never be used anymore; SHA-1 is no longer considered secure, and there
are much better ways to do cryptographic hashing in the kernel.

Remove this header and fold it into <crypto/sha.h> which already
contains constants and functions for SHA-1 (along with SHA-2).

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/sha1_generic.c

@@ -15,7 +15,6 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/mm.h>
-#include <linux/cryptohash.h>
 #include <linux/types.h>
 #include <crypto/sha.h>
 #include <crypto/sha1_base.h>