Convert stm32 entropy driver to configuration based on device tree.
Select HAS_DTS_ENTROPY symbols and configure CONFIG_ENTROPY_NAME
in fixup files.
Since rng node is not enabled (or available) on all boards, it could
happen that symbol ENTROPY_STM32_RNG is not enabled and hence
ENTROPY_HAS_DRIVER not selected which ends up with a symbol
ENTROPY_NAME defined throufg Kconfig selection. Thus, in fixup file,
CONFIG_ENTROPY_NAME is defined only if not already defined.
Additionally, update boards that used to configure entropy by default.
On these boards, enable rng device in device tree and remove Kconfig
related configuration (which should not be part of default
configuration).
Signed-off-by: Erwan Gouriou <erwan.gouriou@linaro.org>
92c4092283