fdts: stm32mp1: remove second QSPI flash instance
fdts: stm32mp1: remove second QSPI flash instance

Remove second flash node as only one must be used
by QSPI NOR driver.

Change-Id: I48189f2fdf4e0455aabe7d4cd9b2f3d36bb9cfb5
Signed-off-by: Lionel Debieve <432d923c5c9ef0a4663385d08cf92d35d2459feb@st.com>

achingupta/arm-trusted-firmware,achingupta/arm-trusted-firmware