interconnect: qcom: osm-l3: Squash common descriptors

Each platform defines their own OSM L3 descriptor, but in practice
there's only two: one for OSM and one for EPSS. Remove the duplicated
definitions.

Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Tested-by: Steev Klimaszewski <steev@kali.org>
Reviewed-by: Sibi Sankar <quic_sibis@quicinc.com>
Link: https://lore.kernel.org/r/20221111032515.3460-3-quic_bjorande@quicinc.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>