x86/Voyager: remove KVM_CLOCK quirk

Voyager has this build-time quirk to exclude KVM_CLOCK:

 	bool "KVM paravirtualized clock"
 	select PARAVIRT
 	select PARAVIRT_CLOCK
	depends on !X86_VOYAGER

Voyager support built into a kernel image does not exclude
KVM paravirt clock support - so remove this quirk.

Signed-off-by: Ingo Molnar <mingo@elte.hu>