kselftest/arm64: Correct logging of FPSIMD register read via ptrace

There's a cut'n'paste error in the logging for our test for reading register
state back via ptrace, correctly say that we did a read instead of a write.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220124175527.3260234-3-broonie@kernel.org


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