nommu: Fix the ARMv6 support for MMU-less platforms

With this patch, Kconfig only selects CPU_HAS_ASID for the MMU
case. It also corrects the typo in the v6wbi_tlb_fns definition in
pgtable-nommu.h.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm/mm/Kconfig

@@ -366,7 +366,7 @@ config CPU_V6
 	select CPU_CACHE_V6
 	select CPU_CACHE_VIPT
 	select CPU_CP15_MMU
-	select CPU_HAS_ASID
+	select CPU_HAS_ASID if MMU
 	select CPU_COPY_V6 if MMU
 	select CPU_TLB_V6 if MMU
 

include/asm-arm/pgtable-nommu.h

@@ -106,7 +106,7 @@ extern int is_in_rom(unsigned long);
 #define v4_tlb_fns	(0)
 #define v4wb_tlb_fns	(0)
 #define v4wbi_tlb_fns	(0)
-#define v6_tlb_fns	(0)
+#define v6wbi_tlb_fns	(0)
 
 #define v3_user_fns	(0)
 #define v4_user_fns	(0)