update paramater names in example

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@44469 15284696-431f-4ddb-bdfa-cd5b030d7da7

raster/simwe/r.sim.water/r.sim.water.html

@@ -136,8 +136,8 @@ r.mapcalc "manning = if(elevation.10m, 0.05, null())"
 r.mapcalc "infilt  = if(elevation.10m, 0.0, null())"
 
 # simulate
-r.sim.water elevin=elevation.10m elev_dxin=elev_dx elev_dyin=elev_dy \
-            rain=rain manin=manning infil=infilt \
+r.sim.water elevation=elevation.10m dx=elev_dx dy=elev_dy \
+            rain=rain man=manning infil=infilt \
             nwalk=5000000 depth=depth
 </pre></div>