mISDN: use NULL pointer instead of plain integer

Fix more than 100 (all remaining in mISDN) sparse warnings:

  drivers/isdn/hardware/mISDN/hfcmulti.c:***:**: warning: Using plain integer as NULL pointer
  drivers/isdn/mISDN/dsp_tones.c:***:**: warning: Using plain integer as NULL pointer
  drivers/isdn/mISDN/dsp_pipeline.c:***:**: warning: Using plain integer as NULL pointer

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/isdn/hardware/mISDN/hfcmulti.c b/drivers/isdn/hardware/mISDN/hfcmulti.c
index 1eac03f39d00..46684e136181 100644
--- a/drivers/isdn/hardware/mISDN/hfcmulti.c
+++ b/drivers/isdn/hardware/mISDN/hfcmulti.c
@@ -887,7 +887,7 @@ vpm_echocan_off(struct hfc_multi *hc, int ch)
 static inline void
 hfcmulti_resync(struct hfc_multi *locked, struct hfc_multi *newmaster, int rm)
 {
-        struct hfc_multi *hc, *next, *pcmmaster = 0;
+        struct hfc_multi *hc, *next, *pcmmaster = NULL;
         u_int *plx_acc_32, pv;
         u_long flags;