mac80111: aes_ccm: cleanup ieee80211_aes_key_setup_encrypt()

This code is written using an anti-pattern called "success handling"
which makes it hard to read, especially if you are used to normal kernel
style.  It should instead be written as a list of directives in a row
with branches for error handling.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/aes_ccm.c

@@ -85,11 +85,15 @@ struct crypto_aead *ieee80211_aes_key_setup_encrypt(const u8 key[],
 		return tfm;
 
 	err = crypto_aead_setkey(tfm, key, key_len);
-	if (!err)
-		err = crypto_aead_setauthsize(tfm, mic_len);
-	if (!err)
-		return tfm;
+	if (err)
+		goto free_aead;
+	err = crypto_aead_setauthsize(tfm, mic_len);
+	if (err)
+		goto free_aead;
+
+	return tfm;
 
+free_aead:
 	crypto_free_aead(tfm);
 	return ERR_PTR(err);
 }