net: sfp: ignore power level 3 prior to SFF-8472 Rev 11.4

Power level 3 was included in SFF-8472 revision 11.9, but this does
not have a compliance code. Use revision 11.4 as the minimum
compliance level instead.

This should avoid any spurious indication of 2W modules.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>