clk: ux500: Provide device enumeration number suffix for SMSC911x

First Ethernet device has a ".0" appended onto the device name. It
appears that we need this in order to obtain the correct clock.

Without this fix Ethernet does not function on Ux500 devices, which is a
regression.

Cc: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
[mturquette@linaro.org: improved changelog]