Select VIRT_TO_BUS directly where needed

In commit 887cbce0ad ("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>

arch/m68k/Kconfig

@@ -8,7 +8,7 @@ config M68K
 	select GENERIC_IRQ_SHOW
 	select GENERIC_ATOMIC64
 	select HAVE_UID16
-	select HAVE_VIRT_TO_BUS
+	select VIRT_TO_BUS
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS
 	select GENERIC_CPU_DEVICES
 	select GENERIC_STRNCPY_FROM_USER if MMU