hwdb: Fix Acer Aspire One AOD270/Packard Bell Dot keymappings

hwdb: Fix Acer Aspire One AOD270/Packard Bell Dot keymappings

The Acer Aspire One AOD270 and the same hardware rebranded as
Packard Bell Dot SC need a couple of keymap fixups:

1. The switch-video-mode key does not do anything. Standard acer-wmi
   maps scancode 0x61 to KEY_IGNORE since typically these events are
   duplicate with the ACPI video bus. But on these models the ACPI video
   bus does not send events for this key, so map it.

2. The Brightness up / down hotkeys send atkbd scancode 0xce / 0xef
   which by default are mapped to KEY_KPPLUSMINUS and KEY_MACRO.
   These actually are duplicate events with the ACPI video bus,
   so map these to KEY_IGNORE.