Merge branch 'DIV_ROUND_UP-uapi'

Nicolas Dichtel says:

====================
uapi: consolidate DIV_ROUND_UP definition

The inital goal was to consolidate ethtool.h uapi header. But I took the
opportunity to remove all duplicate definitions of DIV_ROUND_UP.

v3: add patch #2 and #3

v2: split the patch
    define DIV_ROUND_UP in uapi
====================

Signed-off-by: David S. Miller <davem@davemloft.net>