BUG #10658: FindwxWidgets USE_FILE should not include .cmake extension.

The wxWidgets_USE_FILE variable to be used with the include command
should be set to UsewxWidgets; not UsewxWidgets.cmake.

diff --git a/Modules/FindwxWidgets.cmake b/Modules/FindwxWidgets.cmake
--- a/Modules/FindwxWidgets.cmake
+++ b/Modules/FindwxWidgets.cmake
@@ -188,7 +188,7 @@
   SET(wxWidgets_USE_FILE
     "${wxWidgets_CURRENT_LIST_DIR}/UsewxWidgets.cmake")
 ELSE(EXISTS "${wxWidgets_CURRENT_LIST_DIR}/UsewxWidgets.cmake")
-  SET(wxWidgets_USE_FILE UsewxWidgets.cmake)
+  SET(wxWidgets_USE_FILE UsewxWidgets)
 ENDIF(EXISTS "${wxWidgets_CURRENT_LIST_DIR}/UsewxWidgets.cmake")
 
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