The ezusb_program() is invoked via ->program() in preemptible
context during firmware loading. This is also true for the
->program_init() and ->program_end() callback.

Use ezusb_req_ctx_wait_compl() in ezusb_program_init(),
ezusb_program_bytes(), ezusb_program_end() which are part of firmware
loading during device probe.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201113212252.2243570-6-bigeasy@linutronix.de