Toshiba backlight patch for Fedora kernels

[Hans de Goede]

Hi Josh,

I've a patch for the Toshiba ACPI kernel driver fixing backlight issues
on various models, it fixes these 2 bugs:

https://bugzilla.redhat.com/show_bug.cgi?id=1206036
https://bugzilla.redhat.com/show_bug.cgi?id=1215989

Which are a regression starting with 3.19, since we got 2 bugs in a
short time this likely affects more users.

The fix for this got merged recently:

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/drivers/platform/x86/toshiba_acpi.c?id=358d6a2c3ecae2b22c7d7e61f9d5672557446dfb

I think it would be good to apply this to the Fedora 4.0 / 3.19
kernels, I've attached a version for those (resolves a 1 line conflict
in the #includes). I say I think because although it looks like this
patch will fix issues on various models, it may also introduce issues
on other models which is why I've not added a Cc: stable for upstream.

Still overall I think we should apply this.

Regards,

Hans