[MLIR] Remove LLVMVectorType

[nikic]

Summary

While this claims to be the base class for fixed and scalable vectors, this isn't actually the case. In fact, this appears to be dead code, with the methods on this class only being declared, but not defined anywhere. Probably this is some kind of refactoring leftover?

[rriddle]

Looks like this was missed in https://reviews.llvm.org/D94405

mlir/include/mlir/Dialect/LLVMIR/LLVMTypes.h

public:
   bool areCompatible(DataLayoutEntryListRef oldLayout,
                      DataLayoutEntryListRef newLayout) const;
 
   LogicalResult verifyEntries(DataLayoutEntryListRef entries,
                               Location loc) const;
 };
 
 //===----------------------------------------------------------------------===//
-// LLVMVectorType.
-//===----------------------------------------------------------------------===//
-
-/// LLVM dialect vector type, represents a sequence of elements that can be
-/// processed as one, typically in SIMD context. This is a base class for fixed
-/// and scalable vectors.
-class LLVMVectorType : public Type {
-public:
-  /// Inherit base constructor.
-  using Type::Type;
-
-  /// Support type casting functionality.
-  static bool classof(Type type);
-
-  /// Checks if the given type can be used in a vector type.
-  static bool isValidElementType(Type type);
-
-  /// Returns the element type of the vector.
-  Type getElementType();
-
-  /// Returns the number of elements in the vector.
-  llvm::ElementCount getElementCount();
-
-  /// Verifies that the type about to be constructed is well-formed.
-  static LogicalResult verify(function_ref<InFlightDiagnostic()> emitError,
-                              Type elementType, unsigned numElements);
-};
-
-//===----------------------------------------------------------------------===//
 // LLVMFixedVectorType.
 //===----------------------------------------------------------------------===//
 
 /// LLVM dialect fixed vector type, represents a sequence of elements of known
 /// length that can be processed as one.
 class LLVMFixedVectorType
     : public Type::TypeBase<LLVMFixedVectorType, Type,
                             detail::LLVMTypeAndSizeStorage> {