x86: Rename i386 to x86

arch/x86/lib/pci_type1.c

arch/x86/lib/realmode.c

arch/x86/lib/realmode_switch.S

arch/x86/lib/timer.c

arch/x86/lib/video.c

arch/x86/lib/video_bios.c

arch/x86/lib/zimage.c

boards.cfg

common/exports.c

doc/README-x86

examples/standalone/stubs.c

include/common.h

include/configs/eNET.h

include/exports.h