msm: mdss: remove 64M alignment while requesting bus bandwidth

Currently bus bandwidth update is skipped if new bandwidth request is
within 64M boundary of current request. While enforcing this rule, new
request is changed to 64M aligned and then compared. This results in
higher bandwidth request then necessary which may lead system to higher
clock rate. Fix this by removing 64M alignment to new bandwidth request.

CRs-Fixed: 479711
Change-Id: Ib25afa00b6e9276146ca78a4ce9cbdf3a84288c4
Signed-off-by: Ujwal Patel <ujwalp@codeaurora.org>