Update to v5.15 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-5.15

Test: Builds, and ran bionic unit tests on flame.
Change-Id: I86901ea6d89fb0f7384b90a47bef35d194083c24
diff --git a/libc/kernel/uapi/linux/virtio_scmi.h b/libc/kernel/uapi/linux/virtio_scmi.h
new file mode 100644
index 0000000..7907ed4
--- /dev/null
+++ b/libc/kernel/uapi/linux/virtio_scmi.h
@@ -0,0 +1,27 @@
+/****************************************************************************
+ ****************************************************************************
+ ***
+ ***   This header was automatically generated from a Linux kernel header
+ ***   of the same name, to make information necessary for userspace to
+ ***   call into the kernel available to libc.  It contains only constants,
+ ***   structures, and macros generated from the original header, and thus,
+ ***   contains no copyrightable information.
+ ***
+ ***   To edit the content of this header, modify the corresponding
+ ***   source file (e.g. under external/kernel-headers/original/) then
+ ***   run bionic/libc/kernel/tools/update_all.py
+ ***
+ ***   Any manual change here will be lost the next time this script will
+ ***   be run. You've been warned!
+ ***
+ ****************************************************************************
+ ****************************************************************************/
+#ifndef _UAPI_LINUX_VIRTIO_SCMI_H
+#define _UAPI_LINUX_VIRTIO_SCMI_H
+#include <linux/virtio_types.h>
+#define VIRTIO_SCMI_F_P2A_CHANNELS 0
+#define VIRTIO_SCMI_F_SHARED_MEMORY 1
+#define VIRTIO_SCMI_VQ_TX 0
+#define VIRTIO_SCMI_VQ_RX 1
+#define VIRTIO_SCMI_VQ_MAX_CNT 2
+#endif