crypto: Comment typo

Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

ccan/crypto/sha256/sha256.h

@@ -82,7 +82,7 @@ void sha256_init(struct sha256_ctx *ctx);
 /**
  * SHA256_INIT - initializer for an SHA256 context.
  *
- * This can be used to staticly initialize an SHA256 context (instead
+ * This can be used to statically initialize an SHA256 context (instead
  * of sha256_init()).
  *
  * Example: