Take non-CMIS xcvrs out of lpmode in SFF Manager (#565)

Description
Fix non-CMIS transceivers in down state by bringing them out of low power mode in the SFF Manager Task.
This is intended to work together with the change in sonic-net/sonic-buildimage#20886.

Motivation and Context
Non-CMIS transceivers were not functioning correctly when put into Low Power mode. So XCVRD now brings them out of lpmode.

How Has This Been Tested?
Loaded an image containing this change alongside the change from sonic-net/sonic-buildimage#20886 on an Arista chassis containing a Clearwater2 linecard.
Verified that without this image some interfaces were in a down state but with the image all interfaces came up as expected.

sonic-xcvrd/xcvrd/sff_mgr.py

@@ -14,6 +14,7 @@
 
     from .xcvrd_utilities.port_event_helper import PortChangeObserver
     from .xcvrd_utilities.xcvr_table_helper import XcvrTableHelper
+    from sonic_platform_base.sonic_xcvr.api.public.sff8472 import Sff8472Api
 except ImportError as e:
     raise ImportError(str(e) + " - required module not found")
 
@@ -434,6 +435,18 @@ def task_worker(self):
                 except (AttributeError, NotImplementedError):
                     # Skip if these essential routines are not available
                     continue
+
+                if xcvr_inserted:
+                    set_lp_success = (
+                        sfp.set_lpmode(False) 
+                        if isinstance(api, Sff8472Api) 
+                        else api.set_lpmode(False)
+                    )
+                    if not set_lp_success:
+                        self.log_error(
+                            "{}: Failed to take module out of low power mode.".format(
+                                lport)
+                        )
 
                 if active_lanes is None:
                     active_lanes = self.get_active_lanes_for_lport(lport, subport_idx,