EHCI: HSIC: Set the interrupt threshold control value to 8ms

Modify the maximum rate at which the HSIC host controller will
issue interrupts from 125us to 8ms. This allows HSIC controller
to aggregate all the interrupts generated in 8ms which improves
the power savings without changing the overall performance of the
driver.

CRs-Fixed: 363135, 354475
Change-Id: I17034451b6ec5a55e63054f66ad2818fc1d59824
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
[sboyd: Drop msm driver changes]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>