dma: make Open Firmware device id constant

The match_table field of the struct of_device_id is constant in <linux/of_platform.h>
so it is worth to make the initialization data also constant.

The semantic match that finds this kind of pattern is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
disable decl_init,const_decl_init;
identifier I1, I2, x;
@@
	struct I1 {
	  ...
	  const struct I2 *x;
	  ...
	};
@s@
identifier r.I1, y;
identifier r.x, E;
@@
	struct I1 y = {
	  .x = E,
	};
@c@
identifier r.I2;
identifier s.E;
@@
	const struct I2 E[] = ... ;
@depends on !c@
identifier r.I2;
identifier s.E;
@@
+	const
	struct I2 E[] = ...;
// </smpl>

Signed-off-by: Márton Németh <nm127@freemail.hu>
Cc: Julia Lawall <julia@diku.dk>
Cc: cocci@diku.dk
[dan.j.williams@intel.com: resolved conflict with recent fsldma updates]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/dma/fsldma.c

@@ -1398,7 +1398,7 @@ static int fsldma_of_remove(struct of_device *op)
 	return 0;
 }
 
-static struct of_device_id fsldma_of_ids[] = {
+static const struct of_device_id fsldma_of_ids[] = {
 	{ .compatible = "fsl,eloplus-dma", },
 	{ .compatible = "fsl,elo-dma", },
 	{}

drivers/dma/ppc4xx/adma.c

@@ -4940,7 +4940,7 @@ out_free:
 	return ret;
 }
 
-static struct of_device_id __devinitdata ppc440spe_adma_of_match[] = {
+static const struct of_device_id ppc440spe_adma_of_match[] __devinitconst = {
 	{ .compatible	= "ibm,dma-440spe", },
 	{ .compatible	= "amcc,xor-accelerator", },
 	{},