Do not decode HTTP reason phrase from Dogtag
The HTTP reason phrase sent by Dogtag is assumed to be encoded in
UTF-8, but the encoding used by Tomcat is dependent on system
locale, causing decode errors in some locales.
The reason phrase is optional and will not be sent in a future
version of Tomcat[1], so do not bother decoding and returning it.
[1] https://github.com/apache/tomcat/commit/707ab1c77f3bc189e1c3f29b641506db4c8bce37
Fixes: https://fedorahosted.org/freeipa/ticket/5578
Reviewed-By: Jan Cholasta <jcholast@redhat.com>