target/riscv: Fix checking of whether instruciton at 'pc_next' spans pages

target/riscv: Fix checking of whether instruciton at 'pc_next' spans pages

This bug has a noticeable behavior of falling back to the main loop and
respawning a redundant translation block including a single instruction
when the end address of the compressive instruction is exactly on a page
boundary, and slows down running system performance.

Signed-off-by: Shaobo Song <songshaobo@eswincomputing.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20230220072732.568-1-songshaobo@eswincomputing.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>