package/rauc-hawkbit-updater: fix missing user

Systemd support for the RAUC hawkbit updater was added in

  4aa7a4ad8a (package/rauc-hawkbit-updater: add systemd optional dependency, 2024-07-10)

This installs the RAUC hawkbit updater service, which executes as user
"rauc-hawkbit" [1], which doesn't exist by default.

[1] https://github.com/rauc/rauc-hawkbit-updater/blob/2711c0e02781eb9d97285c87197f1bafef75d0d1/script/rauc-hawkbit-updater.service

Signed-off-by: Gero Schwäricke <gero.schwaericke@sevenlab.de>
Signed-off-by: Julien Olivain <ju.o@free.fr>

package/rauc-hawkbit-updater/rauc-hawkbit-updater.mk

@@ -15,6 +15,10 @@ RAUC_HAWKBIT_UPDATER_CFLAGS = $(TARGET_CFLAGS) -std=c99
 ifeq ($(BR2_PACKAGE_SYSTEMD),y)
 RAUC_HAWKBIT_UPDATER_DEPENDENCIES += systemd
 RAUC_HAWKBIT_UPDATER_CONF_OPTS += -Dsystemd=enabled
+# rauc-hawkbit-updater.service uses this user and group
+define RAUC_HAWKBIT_UPDATER_USERS
+	rauc-hawkbit -1 rauc-hawkbit -1 * - - - RAUC Hawkbit Updater
+endef
 else
 RAUC_HAWKBIT_UPDATER_CONF_OPTS += -Dsystemd=disabled
 endif