v4l2-uvm-test: use the prefered display mode

PD#SWPL-24309

Problem:
currently, the test app use the largest display mode
maybe is not same as the vout display mode.

Solution:
use the prefered display mode

Verify:
v4l2-uvm-test -f 4k.h265 -m 3840x2160 -p 26 -d 0
v4l2-uvm-test -f 4k.h265 -m 3840x2160-60 -p 26 -d 0
v4l2-uvm-test -f 1080p.h265 -m 1920x1080 -p 26 -d 0
v4l2-uvm-test -f 1080p.h265 -m 1920x1080-60 -p 26 -d 0

Change-Id: I4e5042899de9b10c055822372c6025b9fb219e6f
Signed-off-by: Ao Xu <ao.xu@amlogic.com>
2 files changed