arm: dts: k3: Remove unneeded ti, sci-sysreset binding and nodes

This extra binding is non-standard and now unneeded as we bind the
sysreset driver automatically. This matches what is done in Linux
and allows us to more closely match the DTBs. Remove the binding
and all users.

Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Neha Malcom Francis <n-francis@ti.com>
Tested-by: Jonathan Humphreys <j-humphreys@ti.com>