net: phy: realtek: Disable interrupt on Realtek Ethernet PHY drivers

Some Realtek Ethernet PHYs, like RTL8211D(G/N) and RTL8211E(G), have
interrupts enabled by default. If the interrupt is not treated later by
the OS and the PHY's interrupt line is enabled and shared with other
interrupts, the system will get an interrupt storm. This patch disables
the interrupt for PHY devices that use one of the current Realtek
Ethernet PHY drivers. Some of Realtek Ethernet PHYs, such as RTL8211B(L)
have the interrupt masked. In this case, the functionality of the PHY
should not be afected since this patch brings INER and INSR registers to
their default values.

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@freescale.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>