Add enable_sff_mgr flag support for xcvrd (sonic-net#18054)

This PR is a dependency of sonic-net/sonic-platform-daemons#383
HLD of sff_mgr: sonic-net/SONiC#1371

Why I did it
Add enable_xcvrd_sff_mgr flag support for sff_mgr

dockers/docker-platform-monitor/docker-pmon.supervisord.conf.j2

@@ -95,13 +95,23 @@ dependent_startup_wait_for=rsyslogd:running
 
 {% if not skip_xcvrd %}
 [program:xcvrd]
-{% if delay_xcvrd %}
-command={% if skip_xcvrd_cmis_mgr %} bash -c "sleep 30 && python3 /usr/local/bin/xcvrd --skip_cmis_mgr" {% else %} bash -c "sleep 30 && python3 /usr/local/bin/xcvrd" {% endif %}
+{% set base_command = "python3 /usr/local/bin/xcvrd" %}
+{% set options = "" -%}
 
-{% else %}
-command={% if skip_xcvrd_cmis_mgr %} python3 /usr/local/bin/xcvrd --skip_cmis_mgr {% else %} python3 /usr/local/bin/xcvrd {% endif %}
+{% if skip_xcvrd_cmis_mgr %}
+    {%- set options = options + " --skip_cmis_mgr" %}
+{% endif -%}
 
-{% endif %}
+{% if enable_xcvrd_sff_mgr %}
+    {%- set options = options + " --enable_sff_mgr" %}
+{% endif -%}
+
+{% if delay_xcvrd %}
+    {%- set command = "bash -c \"sleep 30 && " ~ base_command ~ options ~ "\"" %}
+{% else %}
+    {%- set command = base_command ~ options %}
+{% endif -%}
+command={{ command }}
 priority=6
 autostart=false
 autorestart=unexpected