blackfin: Add more dcache functions

Add invalidate_dcache_range() and flush_dcache_range() for the blackfin
architecture. Such functions already exist on this arch with different
names, so just forward the call.

This fixes the build of bf609-ezkit board as it uses
drivers/net/designware.c which requires the above functions.

Cc: Sonic Zhang <sonic.adi@gmail.com>, Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vasili Galka <vvv444@gmail.com>

arch/blackfin/lib/cache.c

@@ -111,3 +111,13 @@ int dcache_status(void)
 {
 	return bfin_read_DMEM_CONTROL() & ACACHE_BCACHE;
 }
+
+void invalidate_dcache_range(unsigned long start, unsigned long stop)
+{
+	blackfin_dcache_flush_invalidate_range((const void *)start, (const void *)stop);
+}
+
+void flush_dcache_range(unsigned long start, unsigned long stop)
+{
+	blackfin_dcache_flush_range((const void *)start, (const void *)stop);
+}