Add --print-ir-before-all command line argument

[rikhuijzer]

Adds --print-ir-before-all to the default command line arguments.

The following example gives the same output in arnoldc and xrcf-bin:

tmp.mlir:

func.func @main() -> i32 {
    %0 = arith.constant 1 : i32
    return %0 : i32
}

with

$ xrcf-bin \
    --convert-func-to-llvm \
    --convert-mlir-to-llvmir \
    tmp.mlir \
    --print-ir-before-all

prints

// ----- // IR Dump before convert-func-to-llvm //----- //
module {
  func.func @main() -> i32 {
    %0 = arith.constant 1 : i32
    return %0 : i32
  }
}


// ----- // IR Dump before convert-mlir-to-llvmir //----- //
module {
  llvm.func @main() -> i32 {
    %0 = llvm.mlir.constant(1 : i32) : i32
    llvm.return %0 : i32
  }
}


; ModuleID = 'LLVMDialectModule'
source_filename = "LLVMDialectModule"

define i32 @main() {
  ret i32 1
}

!llvm.module.flags = !{!0}

!0 = !{i32 2, !"Debug Info Version", i32 3}

where the dumps are sent to stderr similar to mlir-opt.