[mlir] Add a new MutableOperandRange class for adding/remove operands

This class allows for mutating an operand range in-place, and provides vector like API for adding/erasing/setting. ODS now uses this class to generate mutable wrappers for named operands, with the name `MutableOperandRange <operand-name>Mutable()`

Differential Revision: https://reviews.llvm.org/D78892