kselftest/arm64: Fix encoding for SVE B16B16 test

[ Upstream commit 69c0d824 ]

The test for SVE_B16B16 had a cut'n'paste of a SME instruction, fix it with
a relevant SVE instruction.

Fixes: 44d10c27 ("kselftest/arm64: Add 2023 DPISA hwcap test coverage")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20241028-arm64-b16b16-test-v1-1-59a4a7449bdf@kernel.org


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>