[libc][stdfix] Implement `idivfx` functions in LLVM libc (#133005)

2025-04-25T11:58:16+00:00

This PR implements the following 8 functions along with the tests.

```c++
int idivr(fract, fract);
long int idivlr(long fract, long fract);
int idivk(accum, accum);
long int idivlk(long accum, long accum);

unsigned int idivur(unsigned fract, unsigned fract);
unsigned long int idivulr(unsigned long fract, unsigned long fract);
unsigned int idivuk(unsigned accum, unsigned accum);
unsigned long int idivulk(unsigned long accum, unsigned long accum);
```

ref: https://www.iso.org/standard/51126.html

Fixes #129125

---------

Signed-off-by: krishna2803

llvm-project.git/libc/src/stdfix/idivulk.cpp, branch main

[libc][stdfix] Implement `idivfx` functions in LLVM libc (#133005)