ring buffer: Use cpu_dcache_is_aliasing()

Upstream Linux commit 8690bbcf3b7 ("Introduce cpu_dcache_is_aliasing()
across all architectures") allows checking whether the architecture has
aliasing data caches more accurately. This will be present in upstream
Linux v6.9 (currently in v6.9-rc3).

I expect this to improve the ring buffer performance on ARM64 and
32-bit ARM with non-aliasing data caches.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I3e29966b8c8cab098d57437a11f1f94c53a9e186