mcexec: --enable-hfi1 to runtime enable/disable HFI1 driver

Conflicts:
	executer/user/mcexec.c

kernel/include/process.h

@@ -552,6 +552,7 @@ struct process {
 
 	long maxrss;
 	long maxrss_children;
+	unsigned long mcexec_flags;
 	/* Memory policy flags and memory specific options */
 	unsigned long mpol_flags;
 	size_t mpol_threshold;