ARM: dts: stm32: Fix GPIO hog flags on DHCOM PicoITX

ARM: dts: stm32: Fix GPIO hog flags on DHCOM PicoITX

The GPIO hog flags are ignored by gpiolib-of.c now, set the flags to 0.
Due to a change in gpiolib-of.c, setting flags to GPIO_ACTIVE_LOW and
using output-low DT property leads to the GPIO being set high instead.

Fixes: ac68793f49de ("ARM: dts: stm32: Add DHCOM based PicoITX board")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Cc: linux-stm32@st-md-mailman.stormreply.com
To: linux-arm-kernel@lists.infradead.org
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>