tests/decode: fix bug, NV12 to I420
tests/decode: fix bug, NV12 to I420

when the width or height of video is odd number,
need to turn it into even number.

Signed-off-by: Lin Hai <2e3a067df9da9f48e50b93ac6db863f66d51f5a2@intel.com>

dspmeng/libyami,zhaobob/libyami,yizhouwei/libyami,yizhouwei/libyami,clearlylin/libyami,chivakker/libyami,01org/libyami,halleyzhao/libyami,stripes416/libyami,dspmeng/libyami,clearlylin/libyami,chivakker/libyami,clearlylin/libyami,seanvk/libyami,stripes416/libyami,uartie/libyami,01org/libyami,lizhong1008/libyami,halleyzhao/libyami,stripes416/libyami,seanvk/libyami,YuJiankang/libyami,seanvk/libyami,dspmeng/libyami,halleyzhao/libyami,uartie/libyami,lizhong1008/libyami,uartie/libyami,zhaobob/libyami,zhaobob/libyami,yizhouwei/libyami,lizhong1008/libyami,chivakker/libyami,YuJiankang/libyami,01org/libyami,halleyzhao/libyami,YuJiankang/libyami