mhi: core: update debugfs entries to include new entries

Include bandwidth scaling status in the states debugfs file.
Also, ensure time is printed consistently in all debugfs files.

Change-Id: Ib0b3c81cf3b4069c2b617d8cc850981eb737d7e7
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>