[CRYPTO]: small sha256 cleanup

Looks like open-coded be_to_cpu.  GCC produces rather poor code for this. 
be_to_cpu produces asm()s which are ~4 times shorter.

Compile-tested only.

I am not sure whether input can be 32bit-unaligned.
If it indeed can be, replace:

((u32*)(input))[I]  ->  get_unaligned( ((u32*)(input))+I )
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

crypto/sha256.c

@@ -63,15 +63,7 @@ static inline u32 RORu32(u32 x, u32 y)
 
 static inline void LOAD_OP(int I, u32 *W, const u8 *input)
 {
-	u32 t1 = input[(4 * I)] & 0xff;
-
-	t1 <<= 8;
-	t1 |= input[(4 * I) + 1] & 0xff;
-	t1 <<= 8;
-	t1 |= input[(4 * I) + 2] & 0xff;
-	t1 <<= 8;
-	t1 |= input[(4 * I) + 3] & 0xff;
-	W[I] = t1;
+	W[I] = __be32_to_cpu( ((u32*)(input))[I] );
 }
 
 static inline void BLEND_OP(int I, u32 *W)