libcrc32c: Move implementation to crypto crc32c

This patch swaps the role of libcrc32c and crc32c.  Previously
the implementation was in libcrc32c and crc32c was a wrapper.
Now the code is in crc32c and libcrc32c just calls the crypto
layer.

The reason for the change is to tap into the algorithm selection
capability of the crypto API so that optimised implementations
such as the one utilising Intel's CRC32C instruction can be
used where available.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/Kconfig

@@ -256,12 +256,10 @@ comment "Digest"
 config CRYPTO_CRC32C
 	tristate "CRC32c CRC algorithm"
 	select CRYPTO_HASH
-	select LIBCRC32C
 	help
 	  Castagnoli, et al Cyclic Redundancy-Check Algorithm.  Used
 	  by iSCSI for header and data digests and by others.
-	  See Castagnoli93.  This implementation uses lib/libcrc32c.
-	  Module will be crc32c.
+	  See Castagnoli93.  Module will be crc32c.
 
 config CRYPTO_CRC32C_INTEL
 	tristate "CRC32c INTEL hardware acceleration"