riscv: Convert interrupt logs to use qemu_log_mask()

Currently we log interrupts and exceptions using the trace backend in
riscv_cpu_do_interrupt(). We also log exceptions using the interrupt log
mask (-d int) in riscv_raise_exception().

This patch converts riscv_cpu_do_interrupt() to log both interrupts and
exceptions with the interrupt log mask, so that both are printed when a
user runs QEMU with -d int.

Backports 69430111ab2fe3f32548a0e70437655d0d937a6a

qemu/target/riscv/op_helper.c

@@ -29,7 +29,6 @@ void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
                                           uint32_t exception, uintptr_t pc)
 {
     CPUState *cs = env_cpu(env);
-    qemu_log_mask(CPU_LOG_INT, "%s: %d\n", __func__, exception);
     cs->exception_index = exception;
     cpu_loop_exit_restore(cs, pc);
 }