ARM: msm: Only compile io.c on platforms that use it

Only the non-dt based MSM platforms need to map memory from their
machine descriptor. Unfortunately it is always compiled if
ARCH_MSM=y and the file also has mach/ includes in it. Since
dt-based MSM platforms aren't actually using anything in this
file just compile io.c on the non-dt based MSM platforms. This
allows the dt-based platforms to participate in the
multi-platform kernel.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>

arch/arm/mach-msm/Makefile

-obj-y += io.o timer.o
+obj-y += timer.o
 obj-y += clock.o
 
 obj-$(CONFIG_MSM_VIC) += irq-vic.o
@@ -8,9 +8,9 @@ obj-$(CONFIG_ARCH_QSD8X50) += sirc.o
 
 obj-$(CONFIG_MSM_PROC_COMM) += proc_comm.o clock-pcom.o vreg.o
 
-obj-$(CONFIG_ARCH_MSM7X00A) += dma.o
-obj-$(CONFIG_ARCH_MSM7X30) += dma.o
-obj-$(CONFIG_ARCH_QSD8X50) += dma.o
+obj-$(CONFIG_ARCH_MSM7X00A) += dma.o io.o
+obj-$(CONFIG_ARCH_MSM7X30) += dma.o io.o
+obj-$(CONFIG_ARCH_QSD8X50) += dma.o io.o
 
 obj-$(CONFIG_MSM_SMD) += smd.o smd_debug.o
 obj-$(CONFIG_MSM_SMD) += last_radio_log.o