dmi: Mark all struct dmi_system_id instances const

... and __initconst if applicable.

Based on similar work for an older kernel in the Grsecurity patch.

[JD: fix toshiba-wmi build]
[JD: add htcpen]
[JD: move __initconst where checkscript wants it]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
diff --git a/drivers/platform/x86/mlx-platform.c b/drivers/platform/x86/mlx-platform.c
index 8f98c21..4f3de2a 100644
--- a/drivers/platform/x86/mlx-platform.c
+++ b/drivers/platform/x86/mlx-platform.c
@@ -247,7 +247,7 @@ static int __init mlxplat_dmi_msn21xx_matched(const struct dmi_system_id *dmi)
 	return 1;
 };
 
-static struct dmi_system_id mlxplat_dmi_table[] __initdata = {
+static const struct dmi_system_id mlxplat_dmi_table[] __initconst = {
 	{
 		.callback = mlxplat_dmi_default_matched,
 		.matches = {