Create asoundlib.h dynamically according to configure options

Create asoundlib.h dynamically according to configure options.
This avoids the inclusion of unused API headers.
Also don't install unused API headers.

include/asoundlib-head.h

@@ -0,0 +1,48 @@
+/**
+ * \file include/asoundlib.h
+ * \brief Application interface library for the ALSA driver
+ * \author Jaroslav Kysela <perex@suse.cz>
+ * \author Abramo Bagnara <abramo@alsa-project.org>
+ * \author Takashi Iwai <tiwai@suse.de>
+ * \date 1998-2001
+ *
+ * Application interface library for the ALSA driver
+ */
+/*
+ *   This library is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU Lesser General Public License as
+ *   published by the Free Software Foundation; either version 2.1 of
+ *   the License, or (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU Lesser General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Lesser General Public
+ *   License along with this library; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ */
+
+#ifndef __ASOUNDLIB_H
+#define __ASOUNDLIB_H
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <assert.h>
+#include <endian.h>
+#include <sys/poll.h>
+#include <errno.h>
+#include <stdarg.h>
+
+#include <alsa/asoundef.h>
+#include <alsa/version.h>
+#include <alsa/global.h>
+#include <alsa/input.h>
+#include <alsa/output.h>
+#include <alsa/error.h>
+#include <alsa/conf.h>