modules: stm32: Rename lib Kconfig symbol

Both ST and STM32 modules where using same HAS_STLIB Kconfig
symbol.
Now that each module is createing is own lib, we need to be able
to distinguish libs.

Depends on zephyrproject-rtos/hal_stm32/pull/52

Signed-off-by: Erwan Gouriou <erwan.gouriou@linaro.org>

drivers/bluetooth/hci/Kconfig

@@ -49,7 +49,7 @@ config BT_SPI
 config BT_STM32_IPM
 	bool "IPM HCI"
 	select USE_STM32_HAL_CORTEX
-	select HAS_STLIB
+	select HAS_STM32LIB
 	help
 	  TODO