mhi: core: calculate times based on given timer frequencies

Query timer frequencies for host and device and calculate time
based on them.

CRs-Fixed: 2377061
Change-Id: I8dba580505870f82bb6e2529d1e01c85c4aafd29
Acked-by: Bhaumik Vasav Bhatt <bbhatt@qti.qualcomm.com>
Signed-off-by: Sujeev Dias <sdias@codeaurora.org>