Fix some Doxygen warnings

lib/krb5/deprecated.c

@@ -488,7 +488,8 @@ krb5_set_error_string(krb5_context context, const char *fmt, ...)
  * Deprecated: use krb5_vset_error_message()
  *
  * @param context Kerberos context
- * @param msg error message to free
+ * @param fmt error message to free
+ * @param args variable argument list vector
  *
  * @return Return an error code or 0.
  *

lib/krb5/sp800-108-kdf.c

@@ -39,7 +39,7 @@
  * As described in SP800-108 5.1 (for HMAC)
  *
  * @param context	Kerberos 5 context
- * @param kdc_K1	Base key material.
+ * @param kdf_K1	Base key material.
  * @param kdf_label	A string that identifies the purpose for the derived key.
  * @param kdf_context   A binary string containing parties, nonce, etc.
  * @param md		Message digest function to use for PRF.

lib/krb5/warn.c

@@ -307,8 +307,8 @@ krb5_vabortx(krb5_context context, const char *fmt, va_list ap)
  * Log a warning to the log, default stderr, and then abort.
  *
  * @param context A Kerberos 5 context
- * @param code error code of the last error
- * @param fmt message to print
+ * @param fmt printf format string of message to print
+ * @param ... arguments for format string
  *
  * @ingroup krb5_error
  */