Added 100Ghz grid check

Author: balram-csco

sonic-xcvrd/xcvrd/xcvrd.py

@@ -1205,6 +1205,13 @@ def config_laser_frequency_validate(self, api, lport, freq, grid=75):
             if chan % 3 != 0:
                 self.log_error("{} configured freq:{} GHz is NOT in 75GHz grid".format(lport, freq))
                 return False
+	elif grid == 100:
+            if (supported_grid >> 5) & 0x1 != 1:
+                self.log_error("{} 100GHz is not supported".format(lport))
+                return False
+            else:
+                self.log_error("{} {}GHz is not supported".format(lport, grid))
+                return False
         return True
 
     def configure_laser_frequency(self, api, lport, freq, grid=75):