Correct path to not create "hack/patches/patches"

Author: NicksWorld

CMakeLists.txt

@@ -451,7 +451,7 @@ if(INSTALL_DATA_FILES)
     install(FILES LICENSE.rst DESTINATION ${DFHACK_USERDOC_DESTINATION})
     install(FILES docs/changelog-placeholder.txt DESTINATION ${DFHACK_USERDOC_DESTINATION} RENAME changelog.txt)
     install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/depends/luacov/src/luacov/ DESTINATION ${DFHACK_DATA_DESTINATION}/lua/luacov)
-    install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/patches DESTINATION ${DFHACK_DATA_DESTINATION}/patches)
+    install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/patches/ DESTINATION ${DFHACK_DATA_DESTINATION}/patches)
 endif()
 
 if(INSTALL_SCRIPTS)