package/rtl8821au: bump version and remove debugging patch

This patch updates rtl8821au to include an upstream commit which
disables debug output, unless a runtime insmod parameter debug=level
is passed when loading the module. This makes the old buildroot patch
to remove hardcoded debug defines unnecessary: as such, it has been
removed.

Signed-off-by: Christian Stewart <christian@paral.in>
Tested-by: Christian Stewart <christian@paral.in>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>