i386 long double math methods

[Joel Sherrill]

Hi

i386-rtems tools do not include long double math routines but Cygwin
does and there is a comment in math.h indicating they have code
elsewhere for these. I went looking for implementations to include in
newlib's libm and it looks like the MIT licensed MUSL has them.

http://git.musl-libc.org/cgit/musl/tree/src/math/i386

Are these OK to use to fill in the long double gaps?

--joel