mISDN: Added layer-1-hold feature

Add IMHOLD_L1 ioctl.
The feature will be disabled on closing.

Signed-off-by: Andreas Eversberg <andreas@eversberg.eu>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/mISDNif.h b/include/linux/mISDNif.h
index cf97459..0b28fd1 100644
--- a/include/linux/mISDNif.h
+++ b/include/linux/mISDNif.h
@@ -229,6 +229,7 @@
 #define OPTION_L2_PTP		2
 #define OPTION_L2_FIXEDTEI	3
 #define OPTION_L2_CLEANUP	4
+#define OPTION_L1_HOLD		5
 
 /* should be in sync with linux/kobject.h:KOBJ_NAME_LEN */
 #define MISDN_MAX_IDLEN		20
@@ -317,6 +318,7 @@
 #define IMCTRLREQ	_IOR('I', 69, int)
 #define IMCLEAR_L2	_IOR('I', 70, int)
 #define IMSETDEVNAME	_IOR('I', 71, struct mISDN_devrename)
+#define IMHOLD_L1	_IOR('I', 72, int)
 
 static inline int
 test_channelmap(u_int nr, u_char *map)