wlcore: testmode: use pm_runtime_resume_and_get() instead of pm_runtime_get_sync()

Using pm_runtime_resume_and_get is more appropriate
for simplifing code

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220413093502.2538316-1-chi.minghao@zte.com.cn