target/ppc: Fix lqarx to set cpu_reserve

target/ppc: Fix lqarx to set cpu_reserve

lqarx does not set cpu_reserve, which causes stqcx. to never succeed.

Cc: qemu-stable@nongnu.org
Fixes: 94bf2658676 ("target/ppc: Use atomic load for LQ and LQARX")
Fixes: 57b38ffd0c6 ("target/ppc: Use tcg_gen_qemu_{ld,st}_i128 for LQARX, LQ, STQ")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230605025445.161932-1-npiggin@gmail.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>