fixed doxygen stripping paths to generated files

doc/Doxyfile.in

@@ -145,6 +145,7 @@ FULL_PATH_NAMES        = YES
 # This tag requires that the tag FULL_PATH_NAMES is set to YES.
 
 STRIP_FROM_PATH        = @PROJECT_SOURCE_DIR@ @PROJECT_BINARY_DIR@
+STRIP_FROM_PATH       += @PROJECT_SOURCE_DIR@/edm4hep
 
 # The STRIP_FROM_INC_PATH tag can be used to strip a user-defined part of the
 # path mentioned in the documentation of a class, which tells the reader which
@@ -154,6 +155,7 @@ STRIP_FROM_PATH        = @PROJECT_SOURCE_DIR@ @PROJECT_BINARY_DIR@
 # using the -I flag.
 
 STRIP_FROM_INC_PATH    = @DOXYGEN_INCLUDE_DIRS@ @PROJECT_BINARY_DIR@/include
+STRIP_FROM_INC_PATH   += @PROJECT_SOURCE_DIR@/edm4hep
 
 # If the SHORT_NAMES tag is set to YES, doxygen will generate much shorter (but
 # less readable) file names. This can be useful is your file systems doesn't