Skip temporary variable for SHA1DC_ALLOW_UNALIGNED_ACCESS

This is the feedback I left on pull request #30[1] turned into a
patch.

1. #30

lib/sha1.c

@@ -1748,7 +1748,6 @@ void SHA1DCSetCallback(SHA1_CTX* ctx, collision_block_callback callback)
 void SHA1DCUpdate(SHA1_CTX* ctx, const char* buf, size_t len)
 {
 	unsigned left, fill;
-	const uint32_t* buffer_to_hash = NULL;
 
 	if (len == 0)
 		return;
@@ -1770,12 +1769,11 @@ void SHA1DCUpdate(SHA1_CTX* ctx, const char* buf, size_t len)
 		ctx->total += 64;
 
 #if defined(SHA1DC_ALLOW_UNALIGNED_ACCESS)
-		buffer_to_hash = (const uint32_t*)buf;
+		sha1_process(ctx, (uint32_t*)(buf));
 #else
-		buffer_to_hash = (const uint32_t*)ctx->buffer;
 		memcpy(ctx->buffer, buf, 64);
+		sha1_process(ctx, (uint32_t*)(ctx->buffer));
 #endif /* defined(SHA1DC_ALLOW_UNALIGNED_ACCESS) */
-		sha1_process(ctx, buffer_to_hash);
 		buf += 64;
 		len -= 64;
 	}