usb_master: Implement bulk programming of flash chip
usb_master: Implement bulk programming of flash chip

This implements replaces the 'writen' stub with a fully functional bulk OUT
implementation.

Signed-off-by: Alexandru Gagniuc <cf8ce030f4bdd6ce49a1b687c7c3ccfa8b34ced2@gmail.com>

mrnuke/qiprog