Add QUIET flag to doxyfile

* get's rid of all the informational stdout printout except
  warnings and errors

Change-Id: I25c085342508e7cf4d24443bb27b8f6f95b707f3

doxyfile

@@ -714,7 +714,7 @@ CITE_BIB_FILES         =
 # messages are off.
 # The default value is: NO.
 
-QUIET                  = NO
+QUIET                  = YES
 
 # The WARNINGS tag can be used to turn on/off the warning messages that are
 # generated to standard error (stderr) by doxygen. If WARNINGS is set to YES