lttng-modules: update to 2.13.1

Bumping lttng-modules to 2.13.1, which fixes the build against 5.16+
kernels.

We drop two previously backported patches.

The following commits are part of this update:

  8c0aec7e Version 2.13.1
  533556cd fix: mm: move kvmalloc-related functions to slab.h (v5.16)
  2f0087ab fix: block: don't call blk_status_to_errno in blk_update_request (v5.16)
  9b092ff2 fix: KVM: MMU: change tracepoints arguments to kvm_page_fault (v5.16)
  036297af fix: KVM: x86: Get exit_reason as part of kvm_x86_ops.get_exit_info (v5.16)
  a029f2a3 fix: isystem: delete global -isystem compile option (v5.16)
  d82de6f3 fix: block: move block-related definitions out of fs.h (v5.16)
  4fabf854 Fix: syscall tracing: missing trigger actions
  38b35aff Warn on event registration/unregistration failure
  e26f740b fix: implicit-int error in EXPORT_SYMBOL_GPL
  c570be0d fix: Revert "Makefile: Enable -Wimplicit-fallthrough for Clang" (v5.15)
  8be4c8a3 fix: cpu/hotplug: Remove deprecated CPU-hotplug functions. (v5.15)

Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>