tcg/arm: Fix goto_tb for large translation blocks

tcg/arm: Fix goto_tb for large translation blocks

Correct arithmetic for separating high and low
on a large negative number.

Cc: qemu-stable@nongnu.org
Fixes: 79ffece4447 ("tcg/arm: Implement direct branch for goto_tb")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1714
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
(cherry picked from commit e41f1825b43796c3508ef309ed0b150ef89acc44)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>