fix(pps): align firmware TOW with current RTL

soc/software/pps_end_to_end_validation/output/stability/stability_report.md

@@ -7,7 +7,7 @@ This report is generated by `stability_analysis.py`. The absolute LNAV epoch pat
 - Current RTL delivered the validated subframe after 9 following bits.
 - With 180 ms postponement, reference error was -0.000032 ms.
 - DUT minus trusted PPS was 32.01 ns. That remainder is the model's configured four-PCLK capture pipeline, not a measured board delay.
-- The production source still defines `POSTPONE_TOW` as 160 ms; this analysis uses the requested 180 ms candidate configuration.
+- Production firmware and this analysis both define `POSTPONE_TOW` as 180 ms for the current RTL delivery semantics.
 
 ## Repository hardware data