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/tracepoint.h b/include/linux/tracepoint.h
index 1fb11da..eede1a7 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -40,7 +40,17 @@
 tracepoint_probe_register_prio(struct tracepoint *tp, void *probe, void *data,
 			       int prio);
 extern int
+tracepoint_probe_register_prio_may_exist(struct tracepoint *tp, void *probe, void *data,
+					 int prio);
+extern int
 tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data);
+static inline int
+tracepoint_probe_register_may_exist(struct tracepoint *tp, void *probe,
+				    void *data)
+{
+	return tracepoint_probe_register_prio_may_exist(tp, probe, data,
+							TRACEPOINT_DEFAULT_PRIO);
+}
 extern void
 for_each_kernel_tracepoint(void (*fct)(struct tracepoint *tp, void *priv),
 		void *priv);
@@ -362,7 +372,7 @@
 		static const char *___tp_str __tracepoint_string = str; \
 		___tp_str;						\
 	})
-#define __tracepoint_string	__attribute__((section("__tracepoint_str")))
+#define __tracepoint_string	__attribute__((section("__tracepoint_str"), used))
 #else
 /*
  * tracepoint_string() is used to save the string address for userspace