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/arch/arm/kernel/signal.h b/arch/arm/kernel/signal.h
index b7b838b..cb076d3 100644
--- a/arch/arm/kernel/signal.h
+++ b/arch/arm/kernel/signal.h
@@ -9,3 +9,5 @@
 	struct siginfo info;
 	struct sigframe sig;
 };
+
+extern struct page *get_signal_page(void);