Fix implementation of KWSYS_PROPERTIES_C

Apply KWSYS_PROPERTIES_C to our C-only library, not the main library.

Change-Id: I550196e6c6bdf613abfa7c7a19ec0b36d7f09553

CMakeLists.txt

@@ -1071,7 +1071,7 @@ IF(KWSYS_ENABLE_C AND KWSYS_C_SRCS)
 
   # Apply user-defined target properties to the library.
   IF(KWSYS_PROPERTIES_C)
-    SET_TARGET_PROPERTIES(${KWSYS_NAMESPACE} PROPERTIES
+    SET_TARGET_PROPERTIES(${KWSYS_NAMESPACE}_c PROPERTIES
       ${KWSYS_PROPERTIES_C}
       )
   ENDIF()