util/macros: rework DIV_ROUND_UP macro
I came cross this possible change while doing code review. The reviewed code added its own div_round_up static inline function instead of reusing the current DIV_ROUND_UP.
Here is a nice blog posts which explains the math behind this change: https://medium.com/@arunistime/how-div-round-up-works-179f1a2113b5
Signed-off-by: Christian Gmeiner christian.gmeiner@gmail.com