fix SF bug 749486

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_4_BRANCH@20936 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

utils/Install/packzip/makefile.b32

@@ -77,13 +77,13 @@ $(OBJU)
 |
 
 clean:
-        -erase *.obj
-        -erase *.exe
-        -erase *.res
-        -erase *.map
-        -erase *.rws
-        -erase *.tds
-        -erase *.il?
+        -$(RM) *.obj
+        -$(RM) *.exe
+        -$(RM) *.res
+        -$(RM) *.map
+        -$(RM) *.rws
+        -$(RM) *.tds
+        -$(RM) *.il?
 
 # individual file dependencies