compiler: centralize all symbol name handling

compiler: centralize all symbol name handling

    Consolidate all symbol name handling into the new file names.cc.  This
    is intended to define all the names that will appear in the generated
    assembly code.  Names that will not appear in the assembly code, such
    as local variable names or label names, remain where they are.

    This consolidation is not intended to change any of the existing
    symbol names.  Tested by building without and without this patch and
    comparing the libgo symbol table.

    Reviewed-on: https://go-review.googlesource.com/68310

	* Make-lang.in (GO_OBJS): Add go/names.o.

From-SVN: r253458