T60/PMH7: move 'touchpad' option to pmh7

T60/PMH7: move 'touchpad' option to pmh7

This option is PMH7 specific, and should be moved there,
so all Notebook utilizing a PMH7 have this option.
For Thinkpads without Touchpad (like the X60), simply
don't add 'touchpad' to cmos.layout.

Change-Id: Icdd0093670d565f1b16e2483aa286f4d63ccc52a
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-on: http://review.coreboot.org/6
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>