greybus: remove obsolete buffer-alignment requirement

Remove unused and unnecessary buffer-alignment define that host driver
were supposed to use.

We can handle unaligned incoming buffers just fine by accessing the
operation-message header via a copy in the receive path, rather than
requiring host drivers to make sure the alignment is correct.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/greybus.h

@@ -79,9 +79,6 @@ struct svc_msg;
  */
 #define GB_BUFFER_HEADROOM_MAX		sizeof(u64)
 
-/* Buffers allocated from the host driver will be aligned to this multiple */
-#define GB_BUFFER_ALIGN	sizeof(u32)
-
 /* Greybus "Host driver" structure, needed by a host controller driver to be
  * able to handle both SVC control as well as "real" greybus messages
  */