Integrate seco-base/lpag/add_c61_sbc

Commit: https://git.seco.com/edgehog/seco-base/-/commit/99bf9bce3af1e41ad83509eaec1e3db77b11d9c6

[CONFIGS][C61] Add C61 board defconfigs

Add defconfig files allowing to build Edgehog Embedded and Things for C61 (SBC-3.5-MX8M-Mini) board based on i.MX8M-Mini processor.