cma: Add support for associating regions by name

Currently, the devicetree lookup code assumes that all
CMA regions are present at a fixed address and uses the
fixed address for associating CMA regions to devices.
This presents a problem for dynamically assigning regions.
Device names get mangled/changed between flattened and
populated devicetree so relying on that is unworkable.
Add a separate name binding to allow lookup later between
devices.

Change-Id: Iaacd9888ea708d7293f1120e2b8c473c5c601f3d
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h
index 285b593..8a1b3a1 100644
--- a/include/linux/dma-contiguous.h
+++ b/include/linux/dma-contiguous.h
@@ -70,7 +70,7 @@
 void dma_contiguous_reserve(phys_addr_t addr_limit);
 
 int dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t *res_base,
-				  phys_addr_t limit);
+				  phys_addr_t limit, const char *name);
 
 int dma_contiguous_add_device(struct device *dev, phys_addr_t base);
 
@@ -91,7 +91,7 @@
 					 phys_addr_t base, phys_addr_t limit)
 {
 	int ret;
-	ret = dma_contiguous_reserve_area(size, &base, limit);
+	ret = dma_contiguous_reserve_area(size, &base, limit, NULL);
 	if (ret == 0)
 		ret = dma_contiguous_add_device(dev, base);
 	return ret;