kselftest/arm64: Don't require FA64 for streaming SVE+ZA tests

kselftest/arm64: Don't require FA64 for streaming SVE+ZA tests

During early development a dependedncy was added on having FA64
available so we could use the full FPSIMD register set in the signal
handler which got copied over into the SSVE+ZA registers test case.
Subsequently the ABI was finialised so the handler is run with streaming
mode disabled meaning this is redundant but the dependency was never
removed, do so now.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230202-arm64-kselftest-sve-za-fa64-v1-1-5c5f3dabe441@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>