Don't use ${CMAKE_INSTALL_PREFIX} as an install destination

Absolute destinations are not necessary, and prevent CPack from working.

CMakeLists.txt

@@ -619,7 +619,7 @@ if(INSTALL_TESTS AND OPENCV_TEST_DATA_PATH AND UNIX)
     configure_file("${CMAKE_CURRENT_SOURCE_DIR}/cmake/templates/opencv_run_all_tests_android.sh.in"
                    "${CMAKE_BINARY_DIR}/unix-install/opencv_run_all_tests.sh" @ONLY)
     install(PROGRAMS "${CMAKE_BINARY_DIR}/unix-install/opencv_run_all_tests.sh"
-            DESTINATION ${CMAKE_INSTALL_PREFIX} COMPONENT tests)
+            DESTINATION . COMPONENT tests)
   else()
     set(OPENCV_PYTHON_TESTS_LIST "")
     if(BUILD_opencv_python)
@@ -648,11 +648,11 @@ endif()
 if(ANDROID OR NOT UNIX)
   install(FILES ${OPENCV_LICENSE_FILE}
         PERMISSIONS OWNER_READ GROUP_READ WORLD_READ
-        DESTINATION ${CMAKE_INSTALL_PREFIX} COMPONENT libs)
+        DESTINATION . COMPONENT libs)
   if(OPENCV_README_FILE)
     install(FILES ${OPENCV_README_FILE}
             PERMISSIONS OWNER_READ GROUP_READ WORLD_READ
-            DESTINATION ${CMAKE_INSTALL_PREFIX} COMPONENT libs)
+            DESTINATION . COMPONENT libs)
   endif()
 endif()
 

cmake/OpenCVGenConfig.cmake

@@ -140,6 +140,6 @@ if(WIN32)
     install(FILES "${CMAKE_BINARY_DIR}/win-install/OpenCVConfig.cmake" DESTINATION "${OpenCV_INSTALL_BINARIES_PREFIX}staticlib" COMPONENT dev)
     install(EXPORT OpenCVModules DESTINATION "${OpenCV_INSTALL_BINARIES_PREFIX}staticlib" FILE OpenCVModules${modules_file_suffix}.cmake COMPONENT dev)
   endif()
-  install(FILES "${CMAKE_BINARY_DIR}/win-install/OpenCVConfig-version.cmake" DESTINATION "${CMAKE_INSTALL_PREFIX}" COMPONENT dev)
-  install(FILES "${OpenCV_SOURCE_DIR}/cmake/OpenCVConfig.cmake" DESTINATION "${CMAKE_INSTALL_PREFIX}/" COMPONENT dev)
+  install(FILES "${CMAKE_BINARY_DIR}/win-install/OpenCVConfig-version.cmake" DESTINATION "." COMPONENT dev)
+  install(FILES "${OpenCV_SOURCE_DIR}/cmake/OpenCVConfig.cmake" DESTINATION "." COMPONENT dev)
 endif()