doxygen: only generate doc for include

doc/Doxyfile.in

@@ -744,8 +744,7 @@ WARN_LOGFILE           =
 # Note: If this tag is empty the current directory is searched.
 
 INPUT                  = @abs_top_srcdir@/include \
-  @abs_top_srcdir@/include/bdsm \
-  @abs_top_srcdir@/src
+  @abs_top_srcdir@/include/bdsm
 
 # This tag can be used to specify the character encoding of the source files
 # that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses