Since commit 96f5c4b2 the needed functions (get_ticks() and get_tbclk() )
are defined for kirkwood CPUs as well. This warning is then not relevant
anymore.

Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
cc: Holger Brunck <holger.brunck@keymile.com>
cc: Prafulla Wadaskar <prafulla@marvell.com>
cc: Albert Aribaud <albert.u.boot@aribaud.net>