autotools: Rewrite configuration in a minimalistic fashion

Drop the per-codec options while at it, since we'll soon include a copy
of the associated headers.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>

Makefile.am

@@ -1,6 +1,34 @@
-AUTOMAKE_OPTIONS = foreign
+# Copyright (C) 2019 Bootlin
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sub license, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice (including the
+# next paragraph) shall be included in all copies or substantial portions
+# of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+# IN NO EVENT SHALL PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR
+# ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 SUBDIRS = src
 
-MAINTAINERCLEANFILES = aclocal.m4 compile config.guess config.sub configure \
-	depcomp install-sh ltmain.sh Makefile.in missing
+MAINTAINERCLEANFILES = aclocal.m4 \
+	compile \
+	config.guess \
+	config.sub \
+	configure \
+	depcomp \
+	install-sh \
+	ltmain.sh \
+	Makefile.in \
+	missing