Fix error at cmake configuration time

I get errors on the 'install' lines saying that it is required to
specify the destinations with CMake 3.13.
This is not required in newer versions apparently?

crnlib/CMakeLists.txt

@@ -211,7 +211,7 @@ add_library(${CRUNCH_LIBRARY_NAME} ${CRUNCH_DEFAULT_LIBRARY_TYPE} $<TARGET_OBJEC
 set_property(TARGET ${CRUNCH_LIBRARY_NAME} PROPERTY POSITION_INDEPENDENT_CODE 1)
 
 if (BUILD_SHARED_LIBS OR BUILD_STATIC_LIBCRN)
-  install(TARGETS ${CRUNCH_LIBRARY_NAME})
+  install(TARGETS ${CRUNCH_LIBRARY_NAME} DESTINATION lib)
 endif()
 
 if ((BUILD_SHARED_LIBS AND BUILD_STATIC_LIBCRN) OR (NOT BUILD_SHARED_LIBS AND BUILD_SHARED_LIBCRN))
@@ -224,5 +224,5 @@ if ((BUILD_SHARED_LIBS AND BUILD_STATIC_LIBCRN) OR (NOT BUILD_SHARED_LIBS AND BU
     set_target_properties(${CRUNCH_OTHER_LIBRARY_NAME} PROPERTIES OUTPUT_NAME ${CRUNCH_LIBRARY_NAME})
   endif()
 
-  install(TARGETS ${CRUNCH_OTHER_LIBRARY_NAME})
+  install(TARGETS ${CRUNCH_OTHER_LIBRARY_NAME} DESTINATION lib)
 endif()

crunch/CMakeLists.txt

@@ -18,5 +18,5 @@ add_executable(${CRUNCH_EXE_NAME} ${CRUNCH_SRCS})
 
 target_link_libraries(${CRUNCH_EXE_NAME} ${CRUNCH_LIBRARY_NAME} ${CMAKE_THREAD_LIBS_INIT})
 
-install(TARGETS ${CRUNCH_EXE_NAME})
+install(TARGETS ${CRUNCH_EXE_NAME} DESTINATION bin)
 set_property(TARGET ${CRUNCH_EXE_NAME} PROPERTY POSITION_INDEPENDENT_CODE 1)