Fix install include dir

external_libs/CMakeLists.txt

@@ -29,7 +29,7 @@ if (DSPFilters_ADDED)
 
 	target_include_directories (
 		DSPFilters PUBLIC $<BUILD_INTERFACE:${DSPFilters_SOURCE_DIR}/shared/DSPFilters/include>
-						  $<INSTALL_INTERFACE:INCLUDE_PATH>
+						  $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/DspFilters>
 	)
 
 	set_property (TARGET DSPFilters PROPERTY FOLDER "external_libs")
@@ -39,7 +39,7 @@ if (DSPFilters_ADDED)
 		VERSION 1.0.0
 		BINARY_DIR ${PROJECT_BINARY_DIR}
 		INCLUDE_DIR ${DSPFilters_SOURCE_DIR}/shared/DSPFilters/include
-		INCLUDE_DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+		INCLUDE_DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/DspFilters
 		NAMESPACE DSPFilters
 		DISABLE_VERSION_SUFFIX YES
 	)