wil6210: specify max. IE length

Expose firmware limit for the max_scan_ie_len;
also do actually set IE's for the probe request

max_scan_ie_len used to be 0, this blocks scan requests with non-zero IE's

Change-Id: I6e33c681da4394485e69e4ab4481b0783154d357
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Git-commit: 77c91295ea537e454113297f6f6fbdfb9f3e67fa
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-testing.git


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