sh: Missing flush_dcache_all() proto in cacheflush.h.

Some boards need this, so provide a definition.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/asm-sh/cpu-sh4/cacheflush.h b/include/asm-sh/cpu-sh4/cacheflush.h
index f563c3b..b3746a9 100644
--- a/include/asm-sh/cpu-sh4/cacheflush.h
+++ b/include/asm-sh/cpu-sh4/cacheflush.h
@@ -17,6 +17,7 @@
  *  so we need them.
  */
 void flush_cache_all(void);
+void flush_dcache_all(void);
 void flush_cache_mm(struct mm_struct *mm);
 #define flush_cache_dup_mm(mm) flush_cache_mm(mm)
 void flush_cache_range(struct vm_area_struct *vma, unsigned long start,