x86/ptrace: Fix documentation for tracehook_report_syscall_entry()

tracehook_report_syscall_entry() is called not only
if %TIF_SYSCALL_TRACE is set, but also if %TIF_SYSCALL_EMU is set,
as appears from x86's entry code.
Signed-off-by: Elvira Khabirova <lineprinter@altlinux.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ldv@altlinux.org
Cc: oleg@redhat.com
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/20181110042209.26333972@akathisiaSigned-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/tracehook.h

@@ -83,8 +83,8 @@ static inline int ptrace_report_syscall(struct pt_regs *regs)
  * tracehook_report_syscall_entry - task is about to attempt a system call
  * @regs:		user register state of current task
  *
- * This will be called if %TIF_SYSCALL_TRACE has been set, when the
- * current task has just entered the kernel for a system call.
+ * This will be called if %TIF_SYSCALL_TRACE or %TIF_SYSCALL_EMU have been set,
+ * when the current task has just entered the kernel for a system call.
  * Full user register state is available here.  Changing the values
  * in @regs can affect the system call number and arguments to be tried.
  * It is safe to block here, preventing the system call from beginning.