greybus: Move the es1_ap_desc.c file to Documentation directory

This .c file isn't needed by the kernel driver, it's there for firmware
developers only, so just move it into the Documentation directory to
reduce confusion.

Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Reviewed-by: Alex Elder <elder@linaro.org>

diff --git a/drivers/staging/greybus/es1_ap_desc.c b/drivers/staging/greybus/Documentation/es1_ap_desc.c
similarity index 100%
rename from drivers/staging/greybus/es1_ap_desc.c
rename to drivers/staging/greybus/Documentation/es1_ap_desc.c