[WP][!!!] (issue7 refract): use correct variable name in declaration

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src/ts/refract/include/refract_para.inc

@@ -57,7 +57,7 @@ c true if plpar_minoff is forced by command line
       logical plpar_forceminoff
 c
 c offset range to calculate reference amplitude for amplitude scaling
-      real plpar_avgxmin, plpar_avgxmax
+      real plpar_avgrefxmin, plpar_avgrefxmax
 c 
 c control modes
 c -------------