greybus: es1-ap-usb: fix svc control pipe flags

The control message flags currently indicate USB_DIR_IN, which
doesn't allow the data phase carrying the SVC message to be
send to the device. Change this to USB_DIR_OUT so our SVC
message buffer reaches the device.

Also, the recipient is USB_RECIP_OTHER but almost all real devices
that handle vendor setup requests seem to set this as
USB_RECIP_INTERFACE. As a result, functionfs-based gadgets don't handle
vendor setup requests with a recipient of OTHER. Change this to
USB_RECIP_INTERFACE to work with the functionfs-based emulator and
this should be no issue for the firmware to implement to match.

Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
greybus: initialize all fields in an SVC handshake message

Currently only the handshake_type is being initialized when
responding to an SVC handshake request. Update this to
explicitly set all header/payload fields appropriately.

Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>