x86/fpu: Remove DEFINE_EVENT(x86_fpu, x86_fpu_copy_src)

x86/fpu: Remove DEFINE_EVENT(x86_fpu, x86_fpu_copy_src)

trace_x86_fpu_copy_src() has no users after:

  22aafe3bcb67 ("x86/fpu: Remove init_task FPU state dependencies, add debugging warning for PF_KTHREAD tasks")

Remove the event.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Chang S . Bae <chang.seok.bae@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250503143843.GA8989@redhat.com