thinkpad_acpi: Add support for HKEY version 0x200

Lenovo Thinkpad devices T460, T460s, T460p, T560, X260 use
HKEY version 0x200 without adaptive keyboard.

HKEY version 0x200 has method MHKA with one parameter value.
Passing parameter value 1 will get hotkey_all_mask (the same like
HKEY version 0x100 without parameter). Passing parameter value 2 to
MHKA method will retrieve hotkey_all_adaptive_mask. If 0 is returned in
that case there is no adaptive keyboard available.

Signed-off-by: Dennis Wassenberg <dennis.wassenberg@secunet.com>
Signed-off-by: Lyude <cpaul@redhat.com>
Tested-by: Lyude <cpaul@redhat.com>
Tested-by: Marco Trevisan <marco@ubuntu.com>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
[dvhart: Keep MHKA error string on one line in new and existing pr_err calls]
Signed-off-by: Darren Hart <dvhart@linux.intel.com>