misc: lattice-ecp3-config: Fix task hung when firmware load failed

When firmware load failed, kernel report task hung as follows:

INFO: task xrun:5191 blocked for more than 147 seconds.
      Tainted: G        W         5.16.0-rc5-next-20211220+ #11
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:xrun            state:D stack:    0 pid: 5191 ppid:   270 flags:0x00000004
Call Trace:
 __schedule+0xc12/0x4b50 kernel/sched/core.c:4986
 schedule+0xd7/0x260 kernel/sched/core.c:6369 (discriminator 1)
 schedule_timeout+0x7aa/0xa80 kernel/time/timer.c:1857
 wait_for_completion+0x181/0x290 kernel/sched/completion.c:85
 lattice_ecp3_remove+0x32/0x40 drivers/misc/lattice-ecp3-config.c:221
 spi_remove+0x72/0xb0 drivers/spi/spi.c:409

lattice_ecp3_remove() wait for signals from firmware loading, but when
load failed, firmware_load() does not send this signal. This cause
device remove hung. Fix it by sending signal even if load failed.

Fixes: 781551df

 ("misc: Add Lattice ECP3 FPGA configuration via SPI")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20211228125522.3122284-1-weiyongjun1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>