Is your feature request related to a problem? Please describe.
On Intel platforms, we need to sign production releases with west sign options "-i" and "-p". Currently SOF's xtensa-build-zephyr.py does not allow passing these options.

Describe the solution you'd like
Option to pass a list of options that suits multivendor usage with "west sign".

@marc-hb May 2022 EDIT: this almost complete. It has NOT been implemented by "passing a list of options to xtensa-build-zephyr.py". It's using west config for west sign instead.

cc:

• xtensa-build-zephyr.py: stop calling west sign, rely on west build #7684
• intel_adsp: move west sign from west flash to earlier west build zephyrproject-rtos/zephyr#54700
• Support 4th level west -c config.ini file(s) zephyrproject-rtos/west#429