[IRDA]: irda parameters warning fixes.

This patch fixes:
  CHECK   /home/kernel/src/net/irda/parameters.c
/home/kernel/src/net/irda/parameters.c:466:2: warning: Using plain integer as NULL pointer
/home/kernel/src/net/irda/parameters.c:520:2: warning: Using plain integer as NULL pointer
/home/kernel/src/net/irda/parameters.c:573:2: warning: Using plain integer as NULL pointer

Signed-off-by: Richard Knutsson <ricknu-0@student.ltu.se>
Signed-off-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/irda/parameters.c b/net/irda/parameters.c
index 2627dad..7183e9e 100644
--- a/net/irda/parameters.c
+++ b/net/irda/parameters.c
@@ -463,7 +463,7 @@
 	int n = 0;
 
 	IRDA_ASSERT(buf != NULL, return ret;);
-	IRDA_ASSERT(info != 0, return ret;);
+	IRDA_ASSERT(info != NULL, return ret;);
 
 	pi_minor = pi & info->pi_mask;
 	pi_major = pi >> info->pi_major_offset;
@@ -517,7 +517,7 @@
 	int n = 0;
 
 	IRDA_ASSERT(buf != NULL, return ret;);
-	IRDA_ASSERT(info != 0, return ret;);
+	IRDA_ASSERT(info != NULL, return ret;);
 
 	pi_minor = buf[n] & info->pi_mask;
 	pi_major = buf[n] >> info->pi_major_offset;
@@ -570,7 +570,7 @@
 	int n = 0;
 
 	IRDA_ASSERT(buf != NULL, return ret;);
-	IRDA_ASSERT(info != 0, return ret;);
+	IRDA_ASSERT(info != NULL, return ret;);
 
 	/*
 	 * Parse all parameters. Each parameter must be at least two bytes