Support cudaq::exp_pauli for quantum devices

[annagrin]

Required prerequisites

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Describe the feature

Description

Currently using exp_pauli on quantum devices fails with the following error:

loc("tmp.cpp":26:5): error: failed to legalize operation 'quake.exp_pauli'
// -----// IR Dump After BasisConversionPass Failed (basis-conversion) ('builtin.module' operation) //----- //
module attributes {llvm.data_layout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128", llvm.triple = "x86_64-unknown-linux-gnu", quake.mangled_name_map = {__nvqpp__mlirgen__function_test_state_param._Z16test_state_paramN5cudaq10pauli_wordE = "_Z16test_state_paramN5cudaq10pauli_wordE"}} {
  func.func @__nvqpp__mlirgen__function_test_state_param._Z16test_state_paramN5cudaq10pauli_wordE() attributes {"cudaq-entrypoint", "cudaq-kernel", no_this} {
    %cst = arith.constant 1.000000e+00 : f64
    %cst_0 = arith.constant 1.5707963267948966 : f64
    %c2_i64 = arith.constant 2 : i64
    %0 = cc.address_of @cstr.585900 : !cc.ptr<!llvm.array<3 x i8>>
    %1 = cc.cast %0 : (!cc.ptr<!llvm.array<3 x i8>>) -> !cc.ptr<i8>
    %2 = cc.stdvec_init %1, %c2_i64 : (!cc.ptr<i8>, i64) -> !cc.charspan
    %3 = quake.alloca !quake.veq<2>
    %4 = quake.extract_ref %3[0] : (!quake.veq<2>) -> !quake.ref
    quake.ry (%cst_0) %4 : (f64, !quake.ref) -> ()
    quake.exp_pauli %cst, %3, %2 : (f64, !quake.veq<2>, !cc.charspan) -> ()
    return
  }
  llvm.mlir.global private constant @cstr.585900("XY\00") {addr_space = 0 : i32}
}


terminate called after throwing an instance of 'std::runtime_error'
  what():  Remote rest platform Quake lowering failed.
Aborted

Suggestion

Implement a compiler pass that converts the expression to gates similar to:
https://github.com/NVIDIA/cuda-quantum/blob/main/runtime/nvqir/CircuitSimulator.h#L135