[NDS32, committed] Fix incorrect settings in sfp-machine.h and t-nds32-newlib for hard fp.

[Chung-Ju Wu]

Hi, all,

For nds32 NDS32_ABI_2FP_PLUS abi design,
some settings and compilation options are required to be adjusted
so that we can build correct libgcc.a library.

Committed as Rev.259645: https://gcc.gnu.org/r259645

libgcc/
        * config/nds32/sfp-machine.h: Fix settings for NDS32_ABI_2FP_PLUS.
        * config/nds32/t-nds32-newlib (HOST_LIBGCC2_CFLAGS): Use -fwrapv.


Best regards,
jasonwucj