hibernation: constify platform_hibernation_ops

Patch against mainline.

Changes since v1: added one hunk; no longer adding "const" qualifier to
pointers in platform_hibernation_ops after seeing
b4144e4f6e3b448d322095ca08af393682a69e33.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index 721d93b..5149c9b 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -498,7 +498,7 @@
 	acpi_enable_all_runtime_gpes();
 }
 
-static struct platform_hibernation_ops acpi_hibernation_ops = {
+static const struct platform_hibernation_ops acpi_hibernation_ops = {
 	.begin = acpi_hibernation_begin,
 	.end = acpi_pm_end,
 	.pre_snapshot = acpi_pm_prepare,
@@ -541,7 +541,7 @@
  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
  * been requested.
  */
-static struct platform_hibernation_ops acpi_hibernation_ops_old = {
+static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
 	.begin = acpi_hibernation_begin_old,
 	.end = acpi_pm_end,
 	.pre_snapshot = acpi_pm_pre_suspend,