microblaze: Support DMA

Add DMA support for Microblaze. There are some part of this new feature:
1. Basic DMA support
2. Enable DMA debug option
3. Setup notifier

Ad 1. dma-mapping come from powerpc and x86 version and it is based on
generic dma-mapping-common.h

Ad 2. DMA support debug features which is used in generic file.
For more information please look at Documentation/DMA-API.txt

Ad 3. notifier is very important to setup dma_ops. Without this part
for example ll_temac driver failed because there are no setup dma operations.

Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/kernel/Makefile b/arch/microblaze/kernel/Makefile
index b07594e..e51bc15 100644
--- a/arch/microblaze/kernel/Makefile
+++ b/arch/microblaze/kernel/Makefile
@@ -14,7 +14,7 @@
 
 extra-y := head.o vmlinux.lds
 
-obj-y += exceptions.o \
+obj-y += dma.o exceptions.o \
 	hw_exception_handler.o init_task.o intc.o irq.o of_device.o \
 	of_platform.o process.o prom.o prom_parse.o ptrace.o \
 	setup.o signal.o sys_microblaze.o timer.o traps.o reset.o