Audio: Volume: Fix a possible overflow in S24_LE format volume

[singalsu]

The AE_SRAI32R() right shift with round could cause the value to go over S24_LE range by one if the gain would be over one or 0 dB (only possible in IPC3). The rounding shift is unnecessary because the gain product is already rounded in the multiply instruction. The SRAI32() instruction does just the shift.

Fixes: f3e3403 ("Audio: Volume: Add IPC4 native Q1.31 mode
and optimize")

[singalsu]

I noticed this overflow risk when working with Level Multiplier. The HiFi5 version has the non-rounding shift, so it didn't need the fix.

[Copilot]

Pull Request Overview

Fixes a potential overflow bug in S24_LE format volume processing where rounding during right shift could cause values to exceed the valid range when gain is over 0 dB.

• Replace AE_SRAI32R() (shift-right with rounding) with AE_SRAI32() (plain shift-right) to prevent overflow
• Update comments to reflect the removal of rounding operation
• Apply fix consistently across all HiFi3/HiFi4 volume processing variants

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/audio/volume/volume_hifi4_with_peakvol.c	Remove rounding from S24_LE shift operation to prevent overflow
src/audio/volume/volume_hifi4.c	Remove rounding from S24_LE shift operation to prevent overflow
src/audio/volume/volume_hifi3_with_peakvol.c	Remove rounding from S24_LE shift operation to prevent overflow
src/audio/volume/volume_hifi3.c	Remove rounding from S24_LE shift operation to prevent overflow

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[lgirdwood]

@singalsu alsa-bat passing. @kv2019i @jsarha pls review