[clang] Add tanf16 builtin and support for tan constrained intrinsic (#93314)

In LLVM, the `llvm.experimental.constrained.cos` and
`llvm.experimental.constrained.sin` intrinsics are used for performing
cosine and sine calculations with additional constraints on
floating-point operations. This behavior is expected for all
floating-point math intrinsics. This change adds these constraints for
the `tan` intrinsic.

-  `Builtins.td` - replace TanF128 with F16F128MathTemplate
- `CGBuiltin.cpp` - map existing tan builtins to `tan` and
`constrained_tan` intrinsic
-   `ConstrainedOps.def` map tan and constrained_tan  to an ISDOpcode.
-  `ISDOpcodes.h` - define tan and strict tan  opcodes

resolves  #91421