Enable STM32 Digital Thermal Sensor driver for stm32mp15xx-dhcor SoMs.

Fixes: 94cafe1b ("ARM: dts: stm32: Add Avenger96 devicetree support based on STM32MP157A")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: linux-stm32@st-md-mailman.stormreply.com
To: linux-arm-kernel@lists.infradead.org
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Alexandre Torgue <alexandre.torgue@st.com>