[RISCV]Add newlib float/long double config options

[Kito Cheng]

Hi Deepa:

Thanks your patch, but it seems like a patch for riscv-gnu-toolchain build
script,
could you send an PR at https://github.com/riscv/riscv-gnu-toolchain :)

On Wed, Oct 31, 2018 at 1:55 PM Deepa Ballari <deepa01012015@gmail.com>
wrote:

> Hello,
> RISCV toolchain config files are modified to add option to newlib that
> allows the floating-point printf support to be split into two
> functions: one for long-double, and one for float.
> Please review the patch file attached.
>
> Thanks & Regards,
> Deepa
>