x86/Voyager: remove VMI Kconfig quirk

x86/Voyager has this build-time quirk:

 	bool "VMI Guest support"
 	select PARAVIRT
 	depends on X86_32
	depends on !X86_VOYAGER

Since VMI is auto-detected (and Voyager will be auto-detected) there's no
reason for this quirk.

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