Select VIRT_TO_BUS directly where needed

In commit 887cbce0adea ("arch Kconfig: centralise ARCH_NO_VIRT_TO_BUS")
I introduced the config sybmol HAVE_VIRT_TO_BUS and selected that where
needed.  I am not sure what I was thinking.  Instead, just directly
select VIRT_TO_BUS where it is needed.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index 5833aa4..8a33ba0 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -9,7 +9,7 @@
 	select HAVE_PERF_EVENTS
 	select HAVE_DMA_ATTRS
 	select HAVE_GENERIC_HARDIRQS
-	select HAVE_VIRT_TO_BUS
+	select VIRT_TO_BUS
 	select GENERIC_IRQ_PROBE
 	select AUTO_IRQ_AFFINITY if SMP
 	select GENERIC_IRQ_SHOW