qemu: Adjust ATTRIBUTE_NONNULL
qemu: Adjust ATTRIBUTE_NONNULL

Commit 7bf679ae removed the @json argument from the qemuMonitorOpen
prototype; however, it did not update the ATTRIBUTE_NONNULL value
which causes a build failure for when checking is enabled such as
when lv_cv_static_analysis is enabled.

Signed-off-by: John Ferlan <87558058f6f829e5ec976c8ef960720af4ff9c7d@redhat.com>

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