Use Delve v0.12.1 instead of master

vendor/github.com/derekparker/delve/proc/ptrace_darwin.go

@@ -0,0 +1,28 @@
+package proc
+
+import sys "golang.org/x/sys/unix"
+
+// PtraceAttach executes the sys.PtraceAttach call.
+func PtraceAttach(pid int) error {
+	return sys.PtraceAttach(pid)
+}
+
+// PtraceDetach executes the PT_DETACH ptrace call.
+func PtraceDetach(tid, sig int) error {
+	return ptrace(sys.PT_DETACH, tid, 1, uintptr(sig))
+}
+
+// PtraceCont executes the PTRACE_CONT ptrace call.
+func PtraceCont(tid, sig int) error {
+	return ptrace(sys.PTRACE_CONT, tid, 1, 0)
+}
+
+// PtraceSingleStep returns PT_STEP ptrace call.
+func PtraceSingleStep(tid int) error {
+	return ptrace(sys.PT_STEP, tid, 1, 0)
+}
+
+func ptrace(request, pid int, addr uintptr, data uintptr) (err error) {
+	_, _, err = sys.Syscall6(sys.SYS_PTRACE, uintptr(request), uintptr(pid), uintptr(addr), uintptr(data), 0, 0)
+	return
+}