[skip ci] Fix doxygen source path

doc/doxygen.conf

@@ -429,7 +429,7 @@ EXTRACT_PACKAGE        = NO
 # included in the documentation.
 # The default value is: NO.
 
-EXTRACT_STATIC         = NO
+EXTRACT_STATIC         = YES
 
 # If the EXTRACT_LOCAL_CLASSES tag is set to YES classes (and structs) defined
 # locally in source files will be included in the documentation. If set to NO
@@ -756,7 +756,9 @@ WARN_LOGFILE           =
 # Note: If this tag is empty the current directory is searched.
 
 INPUT                  = ../doc/main.dox \
-                         ../src
+                         ../src \
+                         ../include/imu \
+                         conf/imu/internal
 
 # 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