Update to v5.11 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-5.11

Test: Built cuttlefish and flame images. Ran bionic unit tests on both.
Change-Id: Ie60337aafad4bda55af99b6c8fe9f56bf2fa787f
diff --git a/libc/kernel/uapi/linux/keyboard.h b/libc/kernel/uapi/linux/keyboard.h
index 570cca9..a05438b 100644
--- a/libc/kernel/uapi/linux/keyboard.h
+++ b/libc/kernel/uapi/linux/keyboard.h
@@ -35,7 +35,6 @@
 #define MAX_NR_OF_USER_KEYMAPS 256
 #define MAX_NR_FUNC 256
 #define KT_LATIN 0
-#define KT_LETTER 11
 #define KT_FN 1
 #define KT_SPEC 2
 #define KT_PAD 3
@@ -46,6 +45,7 @@
 #define KT_META 8
 #define KT_ASCII 9
 #define KT_LOCK 10
+#define KT_LETTER 11
 #define KT_SLOCK 12
 #define KT_DEAD2 13
 #define KT_BRL 14