util: json: Don't bother logging output string in virJSONValueToString
util: json: Don't bother logging output string in virJSONValueToString

We have tests that validate the XML formatter. Additionally almost every
guide tells users to disable JSON logging. Drop logging of output string
in virJSONValueToString.

Signed-off-by: Peter Krempa <2cf5c04c61aa466e4a47bfedc747d17279c72ffc@redhat.com>
Reviewed-by: Laine Stump <c23361c43fbf79fed83e8b76173707b083d6caf5@laine.org>

andreabolognani/libvirt,jardasgit/libvirt,libvirt/libvirt,jfehlig/libvirt,crobinso/libvirt,olafhering/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,zippy2/libvirt,jfehlig/libvirt,eskultety/libvirt,jardasgit/libvirt,nertpinx/libvirt,jardasgit/libvirt,olafhering/libvirt,eskultety/libvirt,jfehlig/libvirt,eskultety/libvirt,libvirt/libvirt,libvirt/libvirt,jfehlig/libvirt,eskultety/libvirt,eskultety/libvirt,fabianfreyer/libvirt,libvirt/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,zippy2/libvirt,zippy2/libvirt,nertpinx/libvirt,crobinso/libvirt,crobinso/libvirt,zippy2/libvirt,crobinso/libvirt,olafhering/libvirt,nertpinx/libvirt,andreabolognani/libvirt,olafhering/libvirt,nertpinx/libvirt,andreabolognani/libvirt,andreabolognani/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt