Bugfix for sTGC TP ROD decoder

This is fixing ATLASRECTS-8085

In this MR:

• real bug fix NSWTP_ROD_Decoder.cxx : segment_packets -> mm_packets
• logic bug fix : creating an RDO per sector, not per elink, in NSWTP_ROD_Decoder
• improved checks for both NSWTP_ROD_Decoder (sTGC TP elinks) and NSWMMTP_ROD_Decoder (MM TP elinks)
• improved and fixed test app (only used privately for debugging purposes)
• last commit is reverting !73878 (merged) since it invalidates valid packets (to be understood better)

@pscholer @dta