x86/cpu/amd: Remove redundant 'break' statement

This break is after the return statement, so it is redundant & confusing,
and should be deleted.
Signed-off-by: Baolin Liu <liubaolin@kylinos.cn>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/396ba14d.2726.189d957b74b.Coremail.liubaolin12138@163.com

arch/x86/kernel/cpu/amd.c

@@ -1001,7 +1001,6 @@ static bool cpu_has_zenbleed_microcode(void)
 
 	default:
 		return false;
-		break;
 	}
 
 	if (boot_cpu_data.microcode < good_rev)