crypto: lib - remove unneeded selection of XOR_BLOCKS

CRYPTO_LIB_CHACHA_GENERIC doesn't need to select XOR_BLOCKS.  It perhaps
was thought that it's needed for __crypto_xor, but that's not the case.

Enabling XOR_BLOCKS is problematic because the XOR_BLOCKS code runs a
benchmark when it is initialized.  That causes a boot time regression on
systems that didn't have it enabled before.

Therefore, remove this unnecessary and problematic selection.

Fixes: e56e1898 ("lib/crypto: add prompts back to crypto libraries")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

lib/crypto/Kconfig

@@ -33,7 +33,6 @@ config CRYPTO_ARCH_HAVE_LIB_CHACHA
 
 config CRYPTO_LIB_CHACHA_GENERIC
 	tristate
-	select XOR_BLOCKS
 	help
 	  This symbol can be depended upon by arch implementations of the
 	  ChaCha library interface that require the generic code as a