Merge changes from topic "TrcDbgExt" into integration
* changes:
feat(plat/fvp): enable trace extension features by default
feat(trf): enable trace filter control register access from lower NS EL
feat(trf): initialize trap settings of trace filter control registers access
feat(sys_reg_trace): enable trace system registers access from lower NS ELs
feat(sys_reg_trace): initialize trap settings of trace system registers access
feat(trbe): enable access to trace buffer control registers from lower NS EL
feat(trbe): initialize trap settings of trace buffer control registers access
