lldpd: fix error "sh: XXXms: bad number"

from commit 3ce909914a12647bec52bcee0a162dd6d158a4f6

The lldpd man page says that "configure lldp tx-interval" can
specify an interval value in milliseconds by appending a "ms" suffix to
the figure. Thus mandating string handling, and not integer comparison.

Tested on 22.03.5

Signed-off-by: Paul Donald <[email protected]>

package/network/services/lldpd/files/lldpd.init

@@ -148,7 +148,7 @@ write_lldpd_conf()
 	[ -n "$lldp_agenttype" ] && echo "configure lldp agent-type $lldp_agenttype" >> "$LLDPD_CONF"
 	[ -n "$lldp_portidsubtype" ] && echo "configure lldp portidsubtype $lldp_portidsubtype" >> "$LLDPD_CONF"
 	[ -n "$lldp_platform" ] && echo "configure system platform" "\"$lldp_platform\"" >> "$LLDPD_CONF"
-	[ $lldp_tx_interval -gt 0 ] && echo "configure lldp tx-interval $lldp_tx_interval" >> "$LLDPD_CONF"
+	[ -n $lldp_tx_interval ] && echo "configure lldp tx-interval $lldp_tx_interval" >> "$LLDPD_CONF"
 	[ $lldp_tx_hold -gt 0 ] && echo "configure lldp tx-hold $lldp_tx_hold" >> "$LLDPD_CONF"
 
 	# Since lldpd's sysconfdir is /tmp, we'll symlink /etc/lldpd.d to /tmp/$LLDPD_CONFS_DIR