remove unused includes

Signed-off-by: Rosen Penev <rosenp@gmail.com>

src/archive/ArchiveList.cxx

@@ -26,7 +26,6 @@
 #include "plugins/ZzipArchivePlugin.hxx"
 
 #include <cassert>
-#include <iterator>
 
 #include <string.h>
 

src/db/update/Archive.cxx

@@ -33,7 +33,6 @@
 #include "util/StringCompare.hxx"
 #include "Log.hxx"
 
-#include <string>
 #include <exception>
 
 #include <string.h>

src/filter/plugins/AutoConvertFilterPlugin.cxx

@@ -23,7 +23,6 @@
 #include "filter/Filter.hxx"
 #include "filter/Prepared.hxx"
 #include "pcm/AudioFormat.hxx"
-#include "util/ConstBuffer.hxx"
 
 #include <cassert>
 #include <memory>

src/input/plugins/AlsaInputPlugin.cxx

@@ -28,12 +28,10 @@
 #include "lib/alsa/NonBlock.hxx"
 #include "lib/alsa/Error.hxx"
 #include "lib/alsa/Format.hxx"
-#include "../InputPlugin.hxx"
 #include "../AsyncInputStream.hxx"
 #include "event/Call.hxx"
 #include "config/Block.hxx"
 #include "util/Domain.hxx"
-#include "util/RuntimeError.hxx"
 #include "util/ASCII.hxx"
 #include "util/DivideString.hxx"
 #include "pcm/AudioParser.hxx"