irda: Convert IRDA_DEBUG to pr_debug

Use the normal kernel debugging mechanism which also
enables dynamic_debug at the same time.

Other miscellanea:

o Remove sysctl for irda_debug
o Remove function tracing like uses (use ftrace instead)
o Coalesce formats
o Realign arguments
o Remove unnecessary OOM messages

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>