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/key.h b/include/linux/key.h
index 6cf8e71..9c26cc9 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -269,6 +269,7 @@
 #define KEY_ALLOC_BUILT_IN		0x0004	/* Key is built into kernel */
 #define KEY_ALLOC_BYPASS_RESTRICTION	0x0008	/* Override the check on restricted keyrings */
 #define KEY_ALLOC_UID_KEYRING		0x0010	/* allocating a user or user session keyring */
+#define KEY_ALLOC_SET_KEEP		0x0020	/* Set the KEEP flag on the key/keyring */
 
 extern void key_revoke(struct key *key);
 extern void key_invalidate(struct key *key);