Omit superfluous use of "CAP"/"SIGNAL" services

The functionality of the former "CAP" and "SIGNAL" services is now
provided by core's "PD" service.

repos/ports/run/virtualbox.run

@@ -34,12 +34,10 @@ set config {
 		<service name="IRQ"/>
 		<service name="IO_MEM"/>
 		<service name="IO_PORT"/>
-		<service name="CAP"/>
 		<service name="PD"/>
 		<service name="RM"/>
 		<service name="CPU"/>
 		<service name="LOG"/>
-		<service name="SIGNAL"/>
 	</parent-provides>
 	<default-route>
 		<any-service> <parent/> <any-child/> </any-service>