[Xtensa] Implement Xtensa Floating Point Option. (#136086)
Implement Xtensa FP Option instructions and lowering
of the base FP operations with tests. Implement UR registers parsing.
Fix loading from constant pool callee, basic block, globaladdress and
jumptable addresses. Also fixed potential memory leakage when several
similar XtensaConstantPoolValue objects are created Fix lowering i32 immediate.
