Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h
index 76cf11e..8a9792a 100644
--- a/include/linux/if_ether.h
+++ b/include/linux/if_ether.h
@@ -24,6 +24,14 @@
 	return (struct ethhdr *)skb_mac_header(skb);
 }
 
+/* Prefer this version in TX path, instead of
+ * skb_reset_mac_header() + eth_hdr()
+ */
+static inline struct ethhdr *skb_eth_hdr(const struct sk_buff *skb)
+{
+	return (struct ethhdr *)skb->data;
+}
+
 static inline struct ethhdr *inner_eth_hdr(const struct sk_buff *skb)
 {
 	return (struct ethhdr *)skb_inner_mac_header(skb);