wil6210: support 40bit DMA addresses

Add the option to support 40bit addresses since some platforms
may not support 48bits but support 40bits

Change-Id: Ie63fed2f9793de348b10932556ea6faf81f93f81
Signed-off-by: Lazar Alexei <qca_ailizaro@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Git-commit: 3dc2c13b5238cef01f36b9ba72e2d1b01862381c
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git


Signed-off-by: Maya Erez <merez@codeaurora.org>