[intelx] Add support for Intel X552 NIC

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/drivers/net/intelx.c

 	PCI_ROM ( 0x8086, 0x1557, "82599en-sfp", "82599 (Single Port SFI Only)", 0 ),
 	PCI_ROM ( 0x8086, 0x1560, "x540t1", "X540-AT2/X540-BT2 (with single port NVM)", 0 ),
 	PCI_ROM ( 0x8086, 0x1563, "x550t2", "X550-T2", 0 ),
+	PCI_ROM ( 0x8086, 0x15ab, "x552", "X552", 0 ),
 	PCI_ROM ( 0x8086, 0x15e5, "x553", "X553", 0 ),
 };