Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/lib/kunit/string-stream-test.c b/lib/kunit/string-stream-test.c
new file mode 100644
index 0000000..110f3a9
--- /dev/null
+++ b/lib/kunit/string-stream-test.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test for struct string_stream.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#include <kunit/test.h>
+#include <linux/slab.h>
+
+#include "string-stream.h"
+
+static void string_stream_test_empty_on_creation(struct kunit *test)
+{
+	struct string_stream *stream = alloc_string_stream(test, GFP_KERNEL);
+
+	KUNIT_EXPECT_TRUE(test, string_stream_is_empty(stream));
+}
+
+static void string_stream_test_not_empty_after_add(struct kunit *test)
+{
+	struct string_stream *stream = alloc_string_stream(test, GFP_KERNEL);
+
+	string_stream_add(stream, "Foo");
+
+	KUNIT_EXPECT_FALSE(test, string_stream_is_empty(stream));
+}
+
+static void string_stream_test_get_string(struct kunit *test)
+{
+	struct string_stream *stream = alloc_string_stream(test, GFP_KERNEL);
+	char *output;
+
+	string_stream_add(stream, "Foo");
+	string_stream_add(stream, " %s", "bar");
+
+	output = string_stream_get_string(stream);
+	KUNIT_ASSERT_STREQ(test, output, "Foo bar");
+}
+
+static struct kunit_case string_stream_test_cases[] = {
+	KUNIT_CASE(string_stream_test_empty_on_creation),
+	KUNIT_CASE(string_stream_test_not_empty_after_add),
+	KUNIT_CASE(string_stream_test_get_string),
+	{}
+};
+
+static struct kunit_suite string_stream_test_suite = {
+	.name = "string-stream-test",
+	.test_cases = string_stream_test_cases
+};
+kunit_test_suites(&string_stream_test_suite);