MIPS: BMIPS: local_r4k___flush_cache_all needs to blast S-cache

local_r4k___flush_cache_all() is missing a special check for BMIPS5000
processors, we need to blast the S-cache, just like other MTI processors
since we have an inclusive cache. We also need an additional __sync() to
make sure this is completed.

Fixes: d74b0172e4 ("MIPS: BMIPS: Add special cache handling in c-r4k.c")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13012/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/mm/c-r4k.c

@@ -447,6 +447,11 @@ static inline void local_r4k___flush_cache_all(void * args)
 		r4k_blast_scache();
 		break;
 
+	case CPU_BMIPS5000:
+		r4k_blast_scache();
+		__sync();
+		break;
+
 	default:
 		r4k_blast_dcache();
 		r4k_blast_icache();