dwc3-msm: Bump up core clock if SS device is connected

If SS part of SS hub enumerates late, then there is a chance
that USB core clock is reduced to HS frequency i.e 66Mhz for power
saving if HS part of hub is enumerated. In this case, SS data transfers
may not work after SS part enumeration due to USB core clock
running < 125Mhz. Hence fix it by bumping up USB core clock to SS frequency
i.e > 125Mhz in host_notifier callback when SS device is added.

Change-Id: Ideb140d99998f349952520f6eed549c7bb2ae10b
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>