spi: spi: Fix queue hang if previous transfer failed

spi: spi: Fix queue hang if previous transfer failed

The queue worker always needs to be kicked one final time after a transfer
is done in order to transition to idle (ctlr->busy = false).

Commit 69fa95905d40 ("spi: Ensure the io_mutex is held until
spi_finalize_current_message()") moved this code into
__spi_pump_messages(), but it was executed only if the transfer was
successful. This condition check causes ctlr-busy to stay true in case of
a failed transfer.
This in turn causes that no new work is ever scheduled to the work queue.

Fixes: 69fa95905d40 ("spi: Ensure the io_mutex is held until spi_finalize_current_message()")
Reported-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220901123630.1098433-1-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>