Update to kernel headers v5.2.

Test: Booted a taimen, ran unit bionic unit tests.
Change-Id: I3522c59793bbcef98ea515996a481d92f14b8816
diff --git a/libc/kernel/uapi/linux/fcntl.h b/libc/kernel/uapi/linux/fcntl.h
index 66f27b6..e2045c8 100644
--- a/libc/kernel/uapi/linux/fcntl.h
+++ b/libc/kernel/uapi/linux/fcntl.h
@@ -60,4 +60,5 @@
 #define AT_STATX_SYNC_AS_STAT 0x0000
 #define AT_STATX_FORCE_SYNC 0x2000
 #define AT_STATX_DONT_SYNC 0x4000
+#define AT_RECURSIVE 0x8000
 #endif