lguest: select CONFIG_TTY to build properly.

Fix kconfig warning for LGUEST_GUEST config by selecting TTY:

warning: (KVMTOOL_TEST_ENABLE && LGUEST_GUEST) selects VIRTIO_CONSOLE which has unmet direct dependencies (VIRTIO && TTY)
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Joe Millenbach <jmillenbach@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/x86/lguest/Kconfig

@@ -2,6 +2,7 @@ config LGUEST_GUEST
 	bool "Lguest guest support"
 	select PARAVIRT
 	depends on X86_32
+	select TTY
 	select VIRTUALIZATION
 	select VIRTIO
 	select VIRTIO_CONSOLE