Merge pull request #3429 from gebart/pr/doxygen-no-man

doc/doxygen/riot.doxyfile: Do not generate man/LaTeX by default

doc/doxygen/Makefile

-doc:
+.PHONY: doc
+doc: html
+
+# by marking html as phony we force make to re-run Doxygen even if the directory exists.
+.PHONY: html
+html:
 	doxygen riot.doxyfile
 
 clean:

doc/doxygen/riot.doxyfile

@@ -1582,7 +1582,7 @@ EXTRA_SEARCH_MAPPINGS  =
 # If the GENERATE_LATEX tag is set to YES doxygen will generate LaTeX output.
 # The default value is: YES.
 
-GENERATE_LATEX         = YES
+GENERATE_LATEX         = NO
 
 # The LATEX_OUTPUT tag is used to specify where the LaTeX docs will be put. If a
 # relative path is entered the value of OUTPUT_DIRECTORY will be put in front of
@@ -1786,7 +1786,7 @@ RTF_EXTENSIONS_FILE    =
 # classes and files.
 # The default value is: NO.
 
-GENERATE_MAN           = YES
+GENERATE_MAN           = NO
 
 # The MAN_OUTPUT tag is used to specify where the man pages will be put. If a
 # relative path is entered the value of OUTPUT_DIRECTORY will be put in front of
@@ -2359,7 +2359,7 @@ DOT_TRANSPARENT        = YES
 # The default value is: NO.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-DOT_MULTI_TARGETS      = NO
+DOT_MULTI_TARGETS      = YES
 
 # If the GENERATE_LEGEND tag is set to YES doxygen will generate a legend page
 # explaining the meaning of the various boxes and arrows in the dot generated