* dw2gencfi.c, dw2gencfi.h: Rewrite from scratch.

    * dw2gencfi.c, dw2gencfi.h: Rewrite from scratch.
        * as.c (main): Always call cfi_finish.
        * config/tc-i386.c (x86_dwarf2_return_column): New.
        (x86_cie_data_alignment): New.
        (md_begin): Set them.
        (tc_x86_cfi_init): Remove.
        (tc_x86_regname_to_dw2regnum): Fix 32-bit register numbers;
        return int, not unsigned long; don't as_bad here.
        (tc_x86_frame_initial_instructions): Streamline; use
        updated api.
        * config/tc-i386.h (tc_cfi_init): Remove.
        (DWARF2_DEFAULT_RETURN_COLUMN): New.
        (DWARF2_CIE_DATA_ALIGNMENT): New.

        * gas/cfi/cfi-i386.d: Update for dw2gencfi rewrite.
        * gas/cfi/cfi-x86_64.d: Likewise.
        * gas/cfi/cfi-i386-2.d: New.
        * gas/cfi/cfi-i386-2.s: New.