ixgbe: Change the lan_id and func fields to a u8 to avoid casts

Since the lan_id and func fields only ever hold small values, make
them u8 to avoid casts used to silence warnings.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
index 8c7e78b..dfdb114 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
@@ -3600,7 +3600,7 @@
 	fw_cmd.hdr.cmd = FW_CEM_CMD_DRIVER_INFO;
 	fw_cmd.hdr.buf_len = FW_CEM_CMD_DRIVER_INFO_LEN;
 	fw_cmd.hdr.cmd_or_resp.cmd_resv = FW_CEM_CMD_RESERVED;
-	fw_cmd.port_num = (u8)hw->bus.func;
+	fw_cmd.port_num = hw->bus.func;
 	fw_cmd.ver_maj = maj;
 	fw_cmd.ver_min = min;
 	fw_cmd.ver_build = build;