Squashed commit of the following:
configs/makerlisp: Update comments about use of serial console.
configs/makerlisp: Add LED support, remove vestiges of button support (the board has no user buttons). Add support for SPI-based MMC/SD card slot.
arch/z80/src/ez80: Fix some link problems.
libs/libc/syslog/lib_syslog.c: The ZDS-II toolchain does not declare va_coy in stdarg.h. I think that the use of va_copy in vsyslog() is no necessary.
configs/makerlisp: Initial configuration directories cloned from ez80f910200zco with little more than naming changes.
Squashed commit of the following:
libs/libxx: Fix some confusing in naming. If the directory is called libxx, then the library must be libxx.a (unless perhaps LIBCXX is selected).
libs/: Fix paths in moved library directories.
libs: Brute force move of libc, libnx, and libxx to libs. Cannot yet build it in that configuration.