dt-bindings: interconnect: OSM L3: Document Milos OSM L3 compatible

Document the OSM L3 found in the Qualcomm Milos SoC.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
Link: https://patch.msgid.link/20260717-milos-cpu-opp-v2-1-428813fafd52@fairphone.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>