Refactor --with-sysconfig, default to /etc/default and /etc/conf.d

Both Debian and Builroot based systems use /etc/default and
Alpine Linux use /etc/conf.d, so let's just put both in by
default.  If the directories exist we monitor them.

The --with-syconfig configure option is now disabled by default.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

contrib/alpine/build.sh

@@ -18,7 +18,6 @@ PKG_CONFIG_LIBDIR=/usr/lib/pkgconfig:/usr/local/lib/pkgconfig ./configure	\
 		 --sysconfdir=/etc		--localstatedir=/var		\
 		 --enable-dbus-plugin		--enable-x11-common-plugin	\
 		 --enable-alsa-utils-plugin	--enable-watchdog		\
-		 --with-sysconfig=/etc/conf.d	--with-hostname=alpine		\
 		 --with-heading="Alpine Linux 3.13"
 
 echo

contrib/debian/build.sh

@@ -27,7 +27,7 @@ echo
     --enable-dbus-plugin              --enable-x11-common-plugin	\
     --enable-alsa-utils-plugin						\
     --with-random-seed=/var/lib/urandom/random-seed			\
-    --with-heading="Debian GNU/Linux" --with-hostname="stretch"
+    --with-heading="Debian GNU/Linux"
 
 if [ $? -ne 0 ]; then
     echo

contrib/void/build.sh

@@ -14,11 +14,11 @@ fi
 # The plugins are optional, but you may need D-Bus and X11 if you want
 # to run X-Window, the other configure flags are however required.
 PKG_CONFIG_LIBDIR=/usr/lib/pkgconfig:/usr/local/lib/pkgconfig ./configure	\
-		 --prefix=/usr                 --exec-prefix=			\
-		 --sysconfdir=/etc             --localstatedir=/var		\
-                 --enable-dbus-plugin          --enable-x11-common-plugin	\
-		 --enable-alsa-utils-plugin    					\
-		 --with-heading="Void Linux"   --with-hostname=void
+		 --prefix=/usr                  --exec-prefix=			\
+		 --sysconfdir=/etc              --localstatedir=/var		\
+                 --enable-dbus-plugin           --enable-x11-common-plugin	\
+		 --enable-alsa-utils-plugin	--enable-watchdog		\
+		 --with-heading="Void Linux"
 
 echo
 echo "*** Building ..."