Stm32L4: No reset exception catch after wakeup

[embitz]

Cortex-m has several exception flags which once triggered will cause EBlink doing a halt with stack unwind to show where the error is.

By default all the flags are enabled. With the -fc option you can enable individual exception flags for fault unwind (fu).

Fault unwind can be switched off, passive on target halt or actively stop on exception. This is the EBlink -fu option.

The fc option is not yet available in the Embitz debug interface settings.