const-qualify FFT-related functions (as much as possible)

[escherstair]

I've been looking to some of the FFT-related functions and trying to find if some of them can be changed const-qualifying some of the input parameters.
I use a bottom-up apòproach (from the most internal to the high-level functions):
an I right if I think that in

CMSIS-DSP/Source/TransformFunctions/arm_rfft_fast_f32.c

Lines 190 to 195 in 30302ca

	/* Prepares data for inverse cfft */
	void merge_rfft_f32(
	const arm_rfft_fast_instance_f32 * S,
	float32_t * p,
	float32_t * pOut)
	{

the input parameter float32_t * p can be const-qualified?

void merge_rfft_f32(
  const arm_rfft_fast_instance_f32 * S,
        const float32_t * p,
        float32_t * pOut)

At a first sight of source code, it seems that the pointed ddta is not changed.
Can someone of the devdelopers double check, please?