Change resource string extension variable RSTEXT to '.rsj'

utils/fpcm/fpcmake.ini

@@ -1041,7 +1041,7 @@ SHAREDLIBEXT=.so
 SHAREDLIBPREFIX=libfp
 STATICLIBPREFIX=libp
 IMPORTLIBPREFIX=libimp
-RSTEXT=.rst
+RSTEXT=.rsj
 # external debug info for executable
 EXEDBGEXT=.dbg
 #DEBUGSYMEXT #for debugger symbol files, define only for targets which has this