usb: dwc3-msm: Increase DBM_MAX_EPS to 8

In newer DBM versions the DBM supports up to 8 EPs.
BM_MAX_EPS needs to be updated to reflect the new value.

Change-Id: I7ff557477e5d85159580bd961e357fe8a41f090e
Signed-off-by: Maya Erez <merez@codeaurora.org>