wil6210: increase timeout for the "echo" command

Sometimes it takes for the firmware more than 20ms to
react on "echo" command after reset. Increase timeout
from 20 to 50ms

Change-Id: Icdba17d83b574bfa345f9d2ce5a5c6698453bb1d
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Git-commit: a54a40dae67e4ee04df4dc36e7b89639131dd8e3
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-testing.git


Signed-off-by: Hamad Kadmany <hkadmany@codeaurora.org>