Improve udev support on non-embedded systems

Embedded Linux systems usually employ BusyBox mdev.  This patch assumes
that all non-embedded systems employ udev.  Adding support for cleaning
up the udev db after the initramfs, or mounting /dev if that not done.
It also runs the udev-finish script at the end.

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

finit.c

@@ -189,6 +189,13 @@ int main(int argc, char* argv[])
 	mount("none", "/proc/bus/usb", "usbfs", 0, NULL);
 	mount("none", "/sys", "sysfs", 0, NULL);
 
+#ifndef EMBEDDED_SYSTEM
+	if (!fismnt("/dev"))
+		mount("udev", "/dev", "devtmpfs", MS_RELATIME, "size=10%,nr_inodes=61156,mode=755");
+	else
+		run_interactive("/sbin/udevadm info --cleanup-db", "Cleaning up udev db");
+#endif
+
 	/* Some systems use /dev/pts */
 	makedir("/dev/pts", 0755);
 	mount("devpts", "/dev/pts", "devpts", 0, "gid=5,mode=620");
@@ -253,6 +260,10 @@ int main(int argc, char* argv[])
 	mount(SYSROOT, "/", NULL, MS_MOVE, NULL);
 #endif
 
+#ifndef EMBEDDED_SYSTEM
+	run_interactive("/lib/udev/udev-finish", "Finalizing udev");
+#endif
+
 	_d("Root FS up, calling hooks ...");
 	plugin_run_hooks(HOOK_ROOTFS_UP);