greybus: Revert "greybus: don't use spin_lock_irq()"

This reverts commit 469fbe5da0229edcb42aa08bef8e10feaa37e6d7.

It isn't correct in places.

Reported-by: Gjorgji Rosikopulos <rosikopulos_gjorgji@projectara.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>