[PATCH 7/9] ppc: silence the compiler warnings

[Chen Qun]

When using -Wimplicit-fallthrough in our CFLAGS, the compiler showed warning:
hw/ppc/ppc.c: In function ‘ppc6xx_set_irq’:
hw/ppc/ppc.c:118:16: warning: this statement may fall through 
[-Wimplicit-fallthrough=]
  118 |             if (level) {
      |                ^
hw/ppc/ppc.c:123:9: note: here
  123 |         case PPC6xx_INPUT_INT:
      |         ^~~~

Add the corresponding "fall through" comment to fix it.

Reported-by: Euler Robot <euler.ro...@huawei.com>
Signed-off-by: Chen Qun <kuhn.chen...@huawei.com>
---
Cc: David Gibson <da...@gibson.dropbear.id.au>
---
 hw/ppc/ppc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c
index 4a11fb1640..f9eb8f21b4 100644
--- a/hw/ppc/ppc.c
+++ b/hw/ppc/ppc.c
@@ -120,6 +120,7 @@ static void ppc6xx_set_irq(void *opaque, int pin, int level)
             } else {
                 cpu_ppc_tb_stop(env);
             }
+            /* fall through */
         case PPC6xx_INPUT_INT:
             /* Level sensitive - active high */
             LOG_IRQ("%s: set the external IRQ state to %d\n",
-- 
2.27.0