kselftest/arm64: Use preferred form for predicate load/stores

The preferred form of the str/ldr for predicate registers with an immediate
of zero is to omit the zero, and the clang built in assembler rejects the
zero immediate. Drop the immediate.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221117114130.687261-1-broonie@kernel.org


Signed-off-by: Will Deacon <will@kernel.org>