soc: espressif: move core identifiers esp32 and esp32s3 to Kconfig.soc

Move the Kconfig symbols SOC_ESP32_PROCPU, SOC_ESP32_APPCPU,
SOC_ESP32S3_PROCPU, and SOC_ESP32S3_APPCPU.

The CPU cluster is defined in espessifc/soc.yml and should therefore
be available in the HWMv2 Kconfig.soc tree.

This will allow sysbuild to test for the CPU cluster when targeting
remote board for a build.

Update espressif boards accordingly.

Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>