* loader/ncch: split NCCH parsing into its own file
* loader/ncch: add support for loading update NCCHs from the SD card
* loader/ncch: fix formatting
* file_sys/ncch_container: Return a value for OpenFile
* loader/ncch: cleanup, always instantiate overlay_ncch to base_ncch
* file_sys/ncch_container: better encryption checks, allow non-app NCCHs to load properly and for the existence of NCCH structures to be checked
* file_sys/ncch_container: pass filepath as a const reference
