mhi: controller: qcom: fix unbalance runtime enable counts

A bug in MHI system suspend function caused the function to exit
prematurely without disabling runtime suspend. The subsequent
runtime resume caused unbalance enable count.

CRs-Fixed: 2291885
Change-Id: I9f45a86fff2caf4ba13236677d1325e7093a1947
Signed-off-by: Sujeev Dias <sdias@codeaurora.org>