ACPI: Ignore _BQC object when registering backlight device

According to acpi spec , the objects of  _BCL and _BCM are required if
integrated LCD is present and supports brightness level .The _BQC is
the optional object. So the _BQC object is ignored when the backlight device
is registered in ACPI video driver.

http://bugzilla.kernel.org/show_bug.cgi?id=10206

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Zhang Rui  <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>