ARM: dts: am3517-evm: Fix misc pinmuxing

[ Upstream commit 942da3af ]

The bootloader for the AM3517 has previously done much of the pin
muxing, but as the bootloader is moving more and more to a model
based on the device tree, it may no longer automatically mux the
pins, so it is necessary to add the pinmuxing to the Linux device
trees so the respective peripherals can remain functional.

Fixes: 6ed1d799 ("ARM: dts: am3517-evm: Add support for UI board and Audio")
Signed-off-by: Adam Ford <aford173@gmail.com>
Message-Id: <20220226214820.747847-1-aford173@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>