When building selftests with RELEASE=1 using GCC compiler, it complaints
about uninitialized err. Fix the problem.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240730231805.1933923-1-andrii@kernel.orgSigned-off-by: Martin KaFai Lau <martin.lau@kernel.org>