dt-bindings: arm: Add Arm C1 cores and PMUs

Add the newly introduced Arm C1-Nano/Pro/Premium/Ultra core and PMU
compatible strings. These cores are part of the Lumex CSS. The new names
are replacing the long lived Cortex-A/X branding going forward.

Signed-off-by: Rob Herring (Arm) <[e-mail]>

Documentation/devicetree/bindings/arm/cpus.yaml

···
       - arm,arm1176jzf-s
       - arm,arm11mpcore
       - arm,armv8 # Only for s/w models
+      - arm,c1-nano
+      - arm,c1-premium
+      - arm,c1-pro
+      - arm,c1-ultra
       - arm,cortex-a5
       - arm,cortex-a7
       - arm,cortex-a8

Documentation/devicetree/bindings/arm/pmu.yaml

···
           - arm,arm1136-pmu
           - arm,arm1176-pmu
           - arm,arm11mpcore-pmu
+          - arm,c1-nano-pmu
+          - arm,c1-premium-pmu
+          - arm,c1-pro-pmu
+          - arm,c1-ultra-pmu
           - arm,cortex-a5-pmu
           - arm,cortex-a7-pmu
           - arm,cortex-a8-pmu