uboot-phytec

stm32f746: to switch on user LED1 & read user button

All discovery boards have one user button & one user LED. Here we are
just reading the button status & switching ON the user LED.

Signed-off-by: Vikas Manocha <vikas.manocha@st.com>
cc: Christophe KERELLO <christophe.kerello@st.com>