Cmake install config fixes

src/ifcgeom/CMakeLists.txt

@@ -14,6 +14,10 @@ add_library(IfcGeom ${SCHEMA_AGNOSTIC_FILES})
 set_target_properties(IfcGeom PROPERTIES
         OUTPUT_NAME "ifcopenshell.geometry"
 )
+target_include_directories(IfcGeom PUBLIC
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/..>
+    $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
+)
 
 if((NOT WIN32) AND BUILD_SHARED_LIBS AND NOT WASM_BUILD AND NOT CREATE_BUNDLE AND NOT CMAKE_INSTALL_RPATH AND COMMAND SET_INSTALL_SELF_RPATH)
     SET_INSTALL_SELF_RPATH(IfcGeom)