arm64/cpuinfo: Remove unnecessary fallthrough annotation

Fallthrough annotations for consecutive default and case labels
are not necessary.
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

arch/arm64/kernel/cpuinfo.c

@@ -327,7 +327,6 @@ static void cpuinfo_detect_icache_policy(struct cpuinfo_arm64 *info)
 		set_bit(ICACHEF_VPIPT, &__icache_flags);
 		break;
 	default:
-		fallthrough;
 	case ICACHE_POLICY_VIPT:
 		/* Assume aliasing */
 		set_bit(ICACHEF_ALIASING, &__icache_flags);