[CRYPTO] padlock: Convert padlock-sha to use crypto_hash

This patch converts padlock-sha to use crypto_hash for its fallback.
It also changes the fallback selection to use selection by type instead
of name.  This is done through the new CRYPTO_ALG_NEED_FALLBACK bit,
which is set if and only if an algorithm needs a fallback of the same
type.

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

include/linux/crypto.h

@@ -42,6 +42,12 @@
 #define CRYPTO_ALG_DYING		0x00000040
 #define CRYPTO_ALG_ASYNC		0x00000080
 
+/*
+ * Set this bit if and only if the algorithm requires another algorithm of
+ * the same type to handle corner cases.
+ */
+#define CRYPTO_ALG_NEED_FALLBACK	0x00000100
+
 /*
  * Transform masks and values (for crt_flags).
  */