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/kfd_ioctl.h b/libc/kernel/uapi/linux/kfd_ioctl.h
index eb355a9..c52ac64 100644
--- a/libc/kernel/uapi/linux/kfd_ioctl.h
+++ b/libc/kernel/uapi/linux/kfd_ioctl.h
@@ -21,7 +21,7 @@
 #include <drm/drm.h>
 #include <linux/ioctl.h>
 #define KFD_IOCTL_MAJOR_VERSION 1
-#define KFD_IOCTL_MINOR_VERSION 5
+#define KFD_IOCTL_MINOR_VERSION 6
 struct kfd_ioctl_get_version_args {
   __u32 major_version;
   __u32 minor_version;