[MIPS] 74K: Assume it will also have an AR bit in config7

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/mm/c-r4k.c

@@ -1009,6 +1009,7 @@ static void __init probe_pcache(void)
 		break;
 	case CPU_24K:
 	case CPU_34K:
+	case CPU_74K:
 		if ((read_c0_config7() & (1 << 16))) {
 			/* effectively physically indexed dcache,
 			   thus no virtual aliases. */