tools/libxc: Fix missing break from c/s b49a7517

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

tools/libxc/xc_domain.c

@@ -1978,6 +1978,7 @@ static int xc_domain_unbind_pt_irq_int(
         break;
     case PT_IRQ_TYPE_SPI:
         bind->u.spi.spi = spi;
+        break;
     default:
         errno = EINVAL;
         return -1;