disp: rotator: set ib, ab bandwidth votes in KBps for interconnect

icc_set_bw api requires ib, ab votes to be in KBps.
The votes received from the userspace will be in the order
of Bps. This change makes the conversion from Bytes to
KiloBytes before applying vote on interconnect path.

Change-Id: I1c02e91be91bda7dcbfe058f3681034a12aedbc5
Signed-off-by: Mahadevan <mahap@codeaurora.org>