Convert drivers over to use virURIPtr for query params

Convert drivers over to use virURIPtr for query params

Convert drivers currently using the qparams APIs, to instead
use the virURIPtr query parameters directly.

* src/esx/esx_util.c, src/hyperv/hyperv_util.c,
  src/remote/remote_driver.c, src/xenapi/xenapi_utils.c: Remove
  use of qparams
* src/util/qparams.h, src/util/qparams.c: Delete
* src/Makefile.am, src/libvirt_private.syms: Remove qparams

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>