Revert "audio: use zephyr/cache.h for cache flush/invalidate"

[kv2019i]

This reverts commit f78acf4.

Fixes build regression with testbuild.

[Copilot]

Pull Request Overview

This PR reverts a previous commit that replaced SOF's native cache operations with Zephyr cache APIs to fix a build regression in testbuild. The revert restores the original cache function calls and header includes across multiple audio subsystem files.

• Replaces zephyr/cache.h includes with rtos/cache.h
• Reverts sys_cache_data_flush_range() calls back to dcache_writeback_region()
• Reverts sys_cache_data_invd_range() calls back to dcache_invalidate_region()

Reviewed Changes

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

File	Description
src/include/sof/audio/audio_stream.h	Reverts header include and cache flush calls in audio stream writeback function
src/audio/copier/copier_ipcgtw.c	Removes zephyr cache header and reverts cache invalidate calls
src/audio/buffers/ring_buffer.c	Removes zephyr cache header and reverts cache operations in ring buffer functions
src/audio/buffers/comp_buffer.c	Moves cache header include and reverts cache flush call in buffer zero function

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[singalsu]

It fixes the issue, thanks Kai!

[tmleman]

Fix fuzz builds.

[kv2019i]

The Internal Intel test is failing on TGL to a failure that seems to be related to test infra. Fail on TGL and "06_00_TestHdaCodecLoopback", exception from test harnesss when "Unhandled Exception: System.BadImageFormatException". FYI @lrudyX @lgirdwood

This is revert of a recent PR so I'd expect no issue in testing.