EHCI: HSIC: fix driver removal function for msm_hsic_host

Upon driver removal function we need to disable the device pm runtime
in order to, first, undo all the logic done in probe and second, to keep
balanced disable depth counter in case of platform driver unbind.

However the removal function can be called also in consequences of
platform_device_del(), in this case the platform device was already
disabled and removed so if we call pm_runtime_disable() again we
decrease the disable_depth for the second time causing for unbalanced
counter.

Therefore we use an if statement to check if the device was already
removed or not.

CRs-Fixed: 445674
Change-Id: I5ff6b20d0f8e811a5c673903ca340f7bcc2e2d78
Signed-off-by: Ido Shayevitz <idos@codeaurora.org>