Fix Doxygen generation and clean-up.

* doc/Doxyfile.in: Amend OUTPUT_DIRECTORY.
* doc/local.mk (html-local): Amend working directory.
(CLEANDIRS): Fix "html", remove "latex".

doc/Doxyfile.in

@@ -30,7 +30,7 @@ PROJECT_NUMBER         = "@PACKAGE_VERSION@"
 # If a relative path is entered, it will be relative to the location
 # where doxygen was started. If left blank the current directory will be used.
 
-OUTPUT_DIRECTORY       = .
+OUTPUT_DIRECTORY       = @top_builddir@/doc
 
 # The OUTPUT_LANGUAGE tag is used to specify the language in which all
 # documentation generated by doxygen is written. Doxygen will use this

doc/local.mk

@@ -124,7 +124,7 @@ DOXYGEN = doxygen
 doc: html
 
 html-local: doc/Doxyfile
-	$(AM_V_GEN) cd doc && $(DOXYGEN)
+	$(AM_V_GEN) $(DOXYGEN) doc/Doxyfile
 
 edit = sed -e 's,@PACKAGE_NAME\@,$(PACKAGE_NAME),g' \
 	   -e 's,@PACKAGE_VERSION\@,$(PACKAGE_VERSION),g' \
@@ -138,4 +138,4 @@ CLEANFILES += doc/Doxyfile
 doc/Doxyfile: $(top_srcdir)/doc/Doxyfile.in
 	$(AM_V_GEN) $(edit) $(top_srcdir)/doc/Doxyfile.in >doc/Doxyfile
 
-CLEANDIRS += html latex
+CLEANDIRS += doc/html