[CRYPTO] api: Split out low-level API

The crypto API is made up of the part facing users such as IPsec and the
low-level part which is used by cryptographic entities such as algorithms.
This patch splits out the latter so that the two APIs are more clearly
delineated.  As a bonus the low-level API can now be modularised if all
algorithms are built as modules.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/internal.h b/crypto/internal.h
index 959e602..26f47d3 100644
--- a/crypto/internal.h
+++ b/crypto/internal.h
@@ -12,7 +12,8 @@
  */
 #ifndef _CRYPTO_INTERNAL_H
 #define _CRYPTO_INTERNAL_H
-#include <linux/crypto.h>
+
+#include <crypto/algapi.h>
 #include <linux/mm.h>
 #include <linux/highmem.h>
 #include <linux/interrupt.h>
@@ -64,9 +65,12 @@
 
 #ifdef CONFIG_PROC_FS
 void __init crypto_init_proc(void);
+void __exit crypto_exit_proc(void);
 #else
 static inline void crypto_init_proc(void)
 { }
+static inline void crypto_exit_proc(void)
+{ }
 #endif
 
 static inline unsigned int crypto_digest_ctxsize(struct crypto_alg *alg,