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/include/linux/string_helpers.h b/include/linux/string_helpers.h
index c289551..fa06dcd 100644
--- a/include/linux/string_helpers.h
+++ b/include/linux/string_helpers.h
@@ -2,6 +2,7 @@
 #ifndef _LINUX_STRING_HELPERS_H_
 #define _LINUX_STRING_HELPERS_H_
 
+#include <linux/ctype.h>
 #include <linux/types.h>
 
 struct file;
@@ -75,8 +76,24 @@
 	return string_escape_str(src, dst, sz, ESCAPE_ANY_NP, only);
 }
 
+static inline void string_upper(char *dst, const char *src)
+{
+	do {
+		*dst++ = toupper(*src);
+	} while (*src++);
+}
+
+static inline void string_lower(char *dst, const char *src)
+{
+	do {
+		*dst++ = tolower(*src);
+	} while (*src++);
+}
+
 char *kstrdup_quotable(const char *src, gfp_t gfp);
 char *kstrdup_quotable_cmdline(struct task_struct *task, gfp_t gfp);
 char *kstrdup_quotable_file(struct file *file, gfp_t gfp);
 
+void kfree_strarray(char **array, size_t n);
+
 #endif