Update to v6.1 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-6.1

Test: Bionic unit tests pass.
Change-Id: I9414fb5e698a9806b85eb09e37d763849f08a468
diff --git a/libc/kernel/uapi/linux/ashmem.h b/libc/kernel/uapi/linux/ashmem.h
index 174667f..88f0e81 100644
--- a/libc/kernel/uapi/linux/ashmem.h
+++ b/libc/kernel/uapi/linux/ashmem.h
@@ -41,4 +41,5 @@
 #define ASHMEM_UNPIN _IOW(__ASHMEMIOC, 8, struct ashmem_pin)
 #define ASHMEM_GET_PIN_STATUS _IO(__ASHMEMIOC, 9)
 #define ASHMEM_PURGE_ALL_CACHES _IO(__ASHMEMIOC, 10)
+#define ASHMEM_GET_FILE_ID _IOR(__ASHMEMIOC, 11, unsigned long)
 #endif