Merge pull request #8042 from haukepetersen/rm_board_x86

boards/qemu-i386/Makefile

boards/qemu-i386/Makefile.features

boards/qemu-i386/Makefile.include

boards/qemu-i386/dist/term.py

boards/qemu-i386/include/board.h

boards/qemu-i386/include/cpu_conf.h

boards/qemu-i386/include/periph_conf.h

boards/qemu-i386/x86_board_init.c

boards/x86-multiboot-common/Makefile

boards/x86-multiboot-common/Makefile.include

boards/x86-multiboot-common/dist/link

boards/x86-multiboot-common/include/multiboot.h

boards/x86-multiboot-common/linker.ld

boards/x86-multiboot-common/startup.c

cpu/x86/Makefile

cpu/x86/Makefile.include

cpu/x86/include/cpu.h

cpu/x86/include/periph_cpu.h

cpu/x86/include/ucontext.h

cpu/x86/include/x86_cmos.h