kselftest/arm64: Fix a couple of spelling mistakes

There are two spelling mistakes in some error messages. Fix them.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240613073429.1797451-1-colin.i.king@gmail.com


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>