mvebu: fix WRT1900AC v1 LED driver module

Update OpenWRT build tree to reflect changes in TLC-591xx LED family driver.

In kernels < 4.0 the driver was present in form of a patch for the TLC-59116 chip,
and was upstreamed later in kernels > 4.0 to support the entire chip family.

Signed-off-by: Sebastian Careba <nitroshift@yahoo.com>
[jow: fix Kconfig symbol name]
Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

SVN-Revision: 48684