[libc] Implement sincosf function correctly rounded to all rounding modes.
Refactor common range reductions and evaluations for sinf, cosf, and
sincosf. Added exhaustive tests for sincosf.
Performance before the patch:
```
System LIBC reciprocal throughput : 30.205
LIBC reciprocal throughput : 30.533
System LIBC latency : 67.961
LIBC latency : 61.564
```
Performance after the patch:
```
System LIBC reciprocal throughput : 30.409
LIBC reciprocal throughput : 20.273
System LIBC latency : 67.527
LIBC latency : 61.959
```
Reviewed By: orex
Differential Revision: https://reviews.llvm.org/D130901
GitOrigin-RevId: 131dda9acc6978aba4740d75ca45f411fbabd726
12 files changed
