powerpc/mm: Move ioremap functions out of pgtable_32/64.c

Create ioremap_32.c and ioremap_64.c and move respective ioremap
functions out of pgtable_32.c and pgtable_64.c

In the meantime, fix a few comments and changes a printk() to
pr_warn(). Also fix a few oversplitted lines.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b5c8b02ccefd4ede64c61b53cf64fb5dacb35740.1566309263.git.christophe.leroy@c-s.fr
diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile
index 29c682f..5e14798 100644
--- a/arch/powerpc/mm/Makefile
+++ b/arch/powerpc/mm/Makefile
@@ -7,7 +7,7 @@
 
 obj-y				:= fault.o mem.o pgtable.o mmap.o \
 				   init_$(BITS).o pgtable_$(BITS).o \
-				   pgtable-frag.o ioremap.o \
+				   pgtable-frag.o ioremap.o ioremap_$(BITS).o \
 				   init-common.o mmu_context.o drmem.o
 obj-$(CONFIG_PPC_MMU_NOHASH)	+= nohash/
 obj-$(CONFIG_PPC_BOOK3S_32)	+= book3s32/