This is an extention of igt_debug_wait_for_keypress that also can have
customized message and return key pressed.

v2: This is actualy a v2. V1 was an extension of original
    igt_debug_wait_for_keypress but it was nacked.

v3: Make [Y/n] check inside aux function as suggested by Daniel.
    Also renaming and adding first use case along with the axu function.

v4: Simplify function name and make it assert pressed key
    is different from n/N as suggested by Daniel.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>