Fast reboot finalizer (#1213)

Updates PR #1196 according to required fast-reboot state-db change.

Update syncd_init_common to check if fast-reboot is enabled according to the new value for FAST_REBOOT entry in STATE_DB.

This PR should come along with the following PRs:
sonic-net/sonic-utilities#2621
sonic-net/sonic-buildimage#13484
sonic-net/sonic-swss-common#742
sonic-net/sonic-platform-daemons#335

This set of PRs solves the issue sonic-net/sonic-buildimage#13251

syncd/scripts/syncd_init_common.sh

@@ -52,8 +52,8 @@ case "$(cat /proc/cmdline)" in
     ;;
   *SONIC_BOOT_TYPE=fast*|*fast-reboot*)
     # check that the key exists
-    SYSTEM_FAST_REBOOT=`sonic-db-cli STATE_DB GET "FAST_RESTART_ENABLE_TABLE|system"`
-    if [[ ${SYSTEM_FAST_REBOOT} == "enable" ]]; then
+    SYSTEM_FAST_REBOOT=`sonic-db-cli STATE_DB hget "FAST_RESTART_ENABLE_TABLE|system" enable`
+    if [[ x"${SYSTEM_FAST_REBOOT}" == x"true" ]]; then
        FAST_REBOOT='yes'
     else
        FAST_REBOOT='no'