arm64: dts: ti: k3-am642-sk|evm: Drop bootargs, add aliases

arm64: dts: ti: k3-am642-sk|evm: Drop bootargs, add aliases

Drop bootargs and add aliases based on base pinout of SK as per [1] and
evm per [2].

Indices chosen attempt to maintain some level of consistency with
existing aliases.

While at this, drop a extra EoL. While this patch could be split, it
seems trivial to add additional cleanup steps.

[1] https://www.ti.com/lit/df/sprr432/sprr432.pdf
[2] https://www.ti.com/lit/zip/swrr171

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Link: https://lore.kernel.org/r/20230414073328.381336-11-nm@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>