net: calxedaxgmac: fix build due to missing __aligned definition

Include linux/compiler.h to fix build error due to missing __aligned
definition.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>

drivers/net/calxedaxgmac.c

@@ -16,6 +16,7 @@
  */
 #include <common.h>
 #include <malloc.h>
+#include <linux/compiler.h>
 #include <linux/err.h>
 #include <asm/io.h>