hyperv: Fix hypervInitConnection error reporting

hyperv: Fix hypervInitConnection error reporting

"%s is not a Hyper-V server" is not a correct generalization of all possible
error conditions of hypervEnumAndPull. For example:

  $ virsh --connect hyperv://localhost/?transport=http
  Enter username for localhost [administrator]:
  Enter administrator's password for localhost: <enters incorrect password>
  error: failed to connect to the hypervisor
  error: internal error: localhost is not a Hyper-V server

This commit removes the general virReportError from hypervInitConnection and
also the "Invalid query" virReportError from hypervSerializeEprParam, which
does not correctly describe the error either (virBufferCheckError has
already set a meaningful error message at that point).

The same scenario with the fix:

  $ virsh --connect hyperv://localhost/?transport=http
  Enter username for localhost [administrator]:
  Enter administrator's password for localhost: <enters incorrect password>
  error: failed to connect to the hypervisor
  error: internal error: Transport error during enumeration: User, password or
  similar was not accepted (26)

Signed-off-by: Ladi Prosek <lprosek@redhat.com>