test: Fix warnings for unused return value

Signed-off-by: Antonio Caggiano <antonio.caggiano@collabora.com>
Reviewed-by: Rohan Garg <rohan.garg@collabora.com>
3 jobs for test-intel in 2 minutes and 14 seconds
Status Job ID Name Coverage
  Check
passed #6595996
clang-format

00:00:08

 
  Build
passed #6595998
aarch64
aarch64

00:02:06

passed #6595997
kvm
x86_64

00:01:55