stm32: rename CONFIG_SOC_STM32 -> CONFIG_SOC_FAMILY_STM32

Use CONFIG_SOC_FAMILY for the top level SoC family. A family
will have different SoCs or different SoC series with multiple
SoCs.
Adding the Family string to the config variable to avoid confusion
between actual SoCs and families and to prevent name collisions.

Change-Id: Ic99a2c1df7850dee3a45641027af82464dd6fadb
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
12 files changed