x86/fpu: Don't reset thread.fpu_counter

x86/fpu: Don't reset thread.fpu_counter

The "else" branch clears ->fpu_counter as a remnant of the lazy FPU
usage counting:

  e07e23e1fd30 ("[PATCH] non lazy "sleazy" fpu implementation")

However, switch_fpu_prepare() does this now so that else branch is
superfluous.

If we do use_eager_fpu(), then this has no effect. Otherwise, if we
actually wanted to prevent fpu preload after the context switch we would
need to reset it unconditionally, even if __thread_has_fpu().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1423252925-14451-2-git-send-email-riel@redhat.com
Signed-off-by: Borislav Petkov <bp@suse.de>