staging: vchiq: Use vchiq.h as the main header file for services

This used to be vchiq_if.h but vchiq.h is more concise for an include
file that will hopefully be in the future in the includes directory.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/20200629150945.10720-46-nsaenzjulienne@suse.de


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>