h8300: use generic ptrace_resume code

Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP.  This implies defining
arch_has_single_step in <asm/ptrace.h> and implementing the
user_enable_single_step and user_disable_single_step functions, which also
causes the breakpoint information to be cleared on fork, which could be
considered a bug fix.

Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL which
it previously wasn't which is consistent with all architectures using the
modern ptrace code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/h8300/platform/h8s/ptrace_h8s.c b/arch/h8300/platform/h8s/ptrace_h8s.c
index e8cd46f..c058ab1 100644
--- a/arch/h8300/platform/h8s/ptrace_h8s.c
+++ b/arch/h8300/platform/h8s/ptrace_h8s.c
@@ -65,13 +65,13 @@
 }
 
 /* disable singlestep */
-void h8300_disable_trace(struct task_struct *child)
+void user_disable_single_step(struct task_struct *child)
 {
 	*(unsigned short *)(child->thread.esp0 + h8300_register_offset[PT_EXR]) &= ~EXR_TRACE;
 }
 
 /* enable singlestep */
-void h8300_enable_trace(struct task_struct *child)
+void user_enable_single_step(struct task_struct *child)
 {
 	*(unsigned short *)(child->thread.esp0 + h8300_register_offset[PT_EXR]) |= EXR_TRACE;
 }