Add configuration files for STM32F7

aidge_export_arm_cortexm/boards/stm32/F7/Drivers/STM32F7xx_HAL_Driver/LICENSE.txt

+This software component is provided to you as part of a software package and
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+the terms of the BSD-3-Clause license shall apply. 
+You may obtain a copy of the BSD-3-Clause at:
+https://opensource.org/licenses/BSD-3-Clause