mfd: Constify struct mfd_cell where possible

As of commit 03e361b25ee8dfb1fd9b890072c23c4aae01c6c7 ("mfd: Stop setting
refcounting pointers in original mfd_cell arrays"), the "cell" parameter of
mfd_add_devices() is "const" again. Hence make all cell data passed to
mfd_add_devices() const where possible.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/vx855.c b/drivers/mfd/vx855.c
index 757ecc63..5cd5661 100644
--- a/drivers/mfd/vx855.c
+++ b/drivers/mfd/vx855.c
@@ -60,7 +60,7 @@
 	},
 };
 
-static struct mfd_cell vx855_cells[] = {
+static const struct mfd_cell vx855_cells[] = {
 	{
 		.name = "vx855_gpio",
 		.num_resources = ARRAY_SIZE(vx855_gpio_resources),