dt-bindings: firmware: amlogic,scpi: Convert to json schema

dt-bindings: firmware: amlogic,scpi: Convert to json schema

Convert/merge the existing text format SCPI binding additions for
amlogic,scpi into the common arm,scpi json scheme.

Couple of things to note:
"amlogic,meson-gxbb-scpi" is always used with "arm,scpi-pre-1.0" and
"amlogic,meson-gxbb-scpi-sensors" is used always with "arm,scpi-sensors"

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20210604205710.1944363-4-sudeep.holla@arm.com
Signed-off-by: Rob Herring <robh@kernel.org>