[MIPS] Add missing 4KEC TLB refill handler

Early 4KEc were MIPS32r1 and therefore need some love to get a TLB
refill handler.
Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/mm/tlbex.c

@@ -307,6 +307,7 @@ static void __cpuinit build_tlb_write_entry(u32 **p, struct uasm_label **l,
 	case CPU_R12000:
 	case CPU_R14000:
 	case CPU_4KC:
+	case CPU_4KEC:
 	case CPU_SB1:
 	case CPU_SB1A:
 	case CPU_4KSC: