board-8084-gpiomux: Add GPIO116 for EPM CS

GPIO116 is used as a chip select for EPM. It is a active low
signal and is being added as part of the blsp configuration.
It uses a FUNC1 and shares similar GPIO configuration properties
for SPI configuration with MOSI, MISO and CLK.

Change-Id: I6245ca7f60c51e82011364c0d49695b6f60498bb
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>