soc: esp32: kconfig: add unsupported revision config

ESP32 SoC has multiple revisions, some of which are not supported
by the current implementation, as such as REV0 and REV1. This PR
adds an option to indicate user that this is not recommended and not
supported.

Signed-off-by: Sylvio Alves <sylvio.alves@espressif.com>