According to technical manual(table 11-24), the DMA of MMCHS0 should be
direct mapped.

Fixes: b5e50906 ("ARM: DTS: am33xx: Use the new DT bindings for the eDMA3")
Signed-off-by: YuTong Chang <mtwget@gmail.com>
Message-Id: <20220620124146.5330-1-mtwget@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>