Imports of package arm64

PathSynopsis
cmd/internal/objabi
cmd/internal/sys
cmd/link/internal/ld
cmd/link/internal/sym
debug/elfPackage elf implements access to ELF object files.
encoding/binaryPackage binary implements simple translation between numbers and byte sequences and encoding and decoding of varints.
fmtPackage fmt implements formatted I/O with functions analogous to C's printf and scanf.
logPackage log implements a simple logging package.