[WP] (stf_issue12): rename gnuplot control file

soutifuamp.gpt was accidentally deleted by target simulclean

src/ts/wf/testcases/Makefile.soutifu

@@ -233,7 +233,7 @@ data%.sff: noisy%.sff stf.fil.xxx
 
 # Display waveform amplitudes
 # ---------------------------
-# Outputs rms and peak-to-peak amplitudes. This is used to provide a reference
+# Output rms and peak-to-peak amplitudes. This is used to provide a reference
 # to adjust the noise amplitude parameter.
 %.amp.xxx: %.sff
 	sigval -format "%F (trace #%NT at %OFF): rms= %RMS P-P= %PPA" \
@@ -241,7 +241,7 @@ data%.sff: noisy%.sff stf.fil.xxx
 %.ampdat.xxx: %.sff
 	sigval -format "%NT %RMS %PPA" $< > $@
 %.amp: %.amp.xxx; cat $<
-soutifuamp.ps: soutifuamp.gpt \
+soutifuamp.ps: plotsoutifuamp.gpt \
   synthetic2lay.ampdat.xxx synthetic2layb.ampdat.xxx \
   data2lay.ampdat.xxx data2layb.ampdat.xxx
 	gnuplot $<