spec: drop R for PyQt4

rpm_spec/core-dom0.spec.in

@@ -90,7 +90,6 @@ Requires:       cronie
 Requires:       scrypt
 # for qubes-hcl-report
 Requires:       dmidecode
-Requires:       PyQt4
 
 # Required for qvm-console* tools
 Requires:       socat