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/asm-arm/asm/unistd-common.h b/libc/kernel/uapi/asm-arm/asm/unistd-common.h
index 060d626..6068bd2 100644
--- a/libc/kernel/uapi/asm-arm/asm/unistd-common.h
+++ b/libc/kernel/uapi/asm-arm/asm/unistd-common.h
@@ -412,4 +412,5 @@
 #define __NR_pidfd_getfd (__NR_SYSCALL_BASE + 438)
 #define __NR_faccessat2 (__NR_SYSCALL_BASE + 439)
 #define __NR_process_madvise (__NR_SYSCALL_BASE + 440)
+#define __NR_epoll_pwait2 (__NR_SYSCALL_BASE + 441)
 #endif