Update PR_* constants

* process.c (prctl_options): Add PR_SET_PTRACER.
diff --git a/process.c b/process.c
index 36f10ba..2c619e7 100644
--- a/process.c
+++ b/process.c
@@ -259,6 +259,9 @@
 #ifdef PR_SET_MM
 	{ PR_SET_MM,		"PR_SET_MM"		},
 #endif
+#ifdef PR_SET_PTRACER
+	{ PR_SET_PTRACER,	"PR_SET_PTRACER"	},
+#endif
 #ifdef PR_SET_CHILD_SUBREAPER
 	{ PR_SET_CHILD_SUBREAPER,	"PR_SET_CHILD_SUBREAPER"	},
 #endif