[mlir][OpenMP][NFC] Remove unused binary operator enum

[shraiysh]

Summary

This patch removes binary operator enum which was introduced with omp.atomic.update. Now the update operation handles update in a region so this is no longer required.

[kiranchandramohan]

LGTM. Could you also add some info to the commit message on why this became redundant (update operation is handled in a region?)?

mlir/include/mlir/Dialect/OpenMP/OpenMPOps.td

def AtomicWriteOp : OpenMP_Op<"atomic.write"> {
   let arguments = (ins OpenMP_PointerLikeType:$address,
                        AnyType:$value,
                        DefaultValuedAttr<I64Attr, "0">:$hint,
                        OptionalAttr<MemoryOrderKindAttr>:$memory_order);
   let hasCustomAssemblyFormat = 1;
   let hasVerifier = 1;
 }
 
-// TODO: autogenerate from OMP.td in future if possible.
-def ATOMIC_BINOP_KIND_ADD : I64EnumAttrCase<"ADD", 0>;
-def ATOMIC_BINOP_KIND_MUL : I64EnumAttrCase<"MUL", 1>;
-def ATOMIC_BINOP_KIND_SUB : I64EnumAttrCase<"SUB", 2>;
-def ATOMIC_BINOP_KIND_DIV : I64EnumAttrCase<"DIV", 3>;
-def ATOMIC_BINOP_KIND_AND : I64EnumAttrCase<"AND", 4>;
-def ATOMIC_BINOP_KIND_OR : I64EnumAttrCase<"OR", 5>;
-def ATOMIC_BINOP_KIND_XOR : I64EnumAttrCase<"XOR", 6>;
-def ATOMIC_BINOP_KIND_SHIFT_RIGHT : I64EnumAttrCase<"SHIFTR", 7>;
-def ATOMIC_BINOP_KIND_SHIFT_LEFT : I64EnumAttrCase<"SHIFTL", 8>;
-def ATOMIC_BINOP_KIND_MAX : I64EnumAttrCase<"MAX", 9>;
-def ATOMIC_BINOP_KIND_MIN : I64EnumAttrCase<"MIN", 10>;
-def ATOMIC_BINOP_KIND_EQV : I64EnumAttrCase<"EQV", 11>;
-def ATOMIC_BINOP_KIND_NEQV : I64EnumAttrCase<"NEQV", 12>;
-
-def AtomicBinOpKindAttr : I64EnumAttr<
-    "AtomicBinOpKind", "BinOp for Atomic Updates",
-    [ATOMIC_BINOP_KIND_ADD, ATOMIC_BINOP_KIND_MUL, ATOMIC_BINOP_KIND_SUB,
-     ATOMIC_BINOP_KIND_DIV, ATOMIC_BINOP_KIND_AND, ATOMIC_BINOP_KIND_OR,
-     ATOMIC_BINOP_KIND_XOR, ATOMIC_BINOP_KIND_SHIFT_RIGHT,
-     ATOMIC_BINOP_KIND_SHIFT_LEFT, ATOMIC_BINOP_KIND_MAX,
-     ATOMIC_BINOP_KIND_MIN, ATOMIC_BINOP_KIND_EQV, ATOMIC_BINOP_KIND_NEQV]> {
-  let cppNamespace = "::mlir::omp";
-  let stringToSymbolFnName = "AtomicBinOpKindToEnum";
-  let symbolToStringFnName = "AtomicBinOpKindToString";
-}
-
 def AtomicUpdateOp : OpenMP_Op<"atomic.update",
                                [SingleBlockImplicitTerminator<"YieldOp">]> {
 
   let summary = "performs an atomic update";
 
   let description = [{
     This operation performs an atomic update.