[S390] zcrypt: Comments and kernel-doc cleanup

Comments, which suggested to be kernel-doc but were not in the right
formatting, have been corrected. Additionally some minor cleanup in
the comments has been done.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

drivers/s390/crypto/zcrypt_pcixcc.c

@@ -501,7 +501,7 @@ static int convert_type86_ica(struct zcrypt_device *zdev,
 	reply_len = msg->length - 2;
 	if (reply_len > outputdatalength)
 		return -EINVAL;
-	/**
+	/*
 	 * For all encipher requests, the length of the ciphertext (reply_len)
 	 * will always equal the modulus length. For MEX decipher requests
 	 * the output needs to get padded. Minimum pad size is 10.