usb: musb: cppi_dma.c: use DIV_ROUND_UP macro in cppi_next_(r|t)x_segment()

DIV_ROUND_UP is bit useful than series of "/" and "%" operations.
Replace "/%" sequence with DIV_ROUND_UP macro.

Signed-off-by: Ivan Safonov <insafonov@gmail.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>