microblaze: switch to GENERIC_PCI_IOMAP

microblaze copied pci_iomap from generic code, probably to avoid
pulling the rest of iomap.c in.  Since that's in
a separate file now, we can reuse the common implementation.

The only difference is handling of nocache flag,
that turns out to be done correctly by the
generic code since arch/microblaze/include/asm/io.h
defines ioremap_nocache same as ioremap.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index e446bab..f0eead7 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -17,6 +17,7 @@
 	select HAVE_GENERIC_HARDIRQS
 	select GENERIC_IRQ_PROBE
 	select GENERIC_IRQ_SHOW
+	select GENERIC_PCI_IOMAP
 
 config SWAP
 	def_bool n