Revert "microblaze: Kill NET_SKB_PAD and NET_IP_ALIGN overrides."

This reverts commit 39e0786d.

On request from microblaze developers, they are going to handle
this differently.
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/microblaze/include/asm/system.h

@@ -97,4 +97,14 @@ extern struct dentry *of_debugfs_root;
 
 #define arch_align_stack(x) (x)
 
+/*
+ * MicroBlaze doesn't handle unaligned accesses in hardware.
+ *
+ * Based on this we force the IP header alignment in network drivers.
+ * We also modify NET_SKB_PAD to be a cacheline in size, thus maintaining
+ * cacheline alignment of buffers.
+ */
+#define NET_IP_ALIGN	2
+#define NET_SKB_PAD	L1_CACHE_BYTES
+
 #endif /* _ASM_MICROBLAZE_SYSTEM_H */