Staging: comedi: Fix coding style issues in ni_tiocmd.c

This patch fixes the following issues in ni_tiocmd.c:

WARNING: braces {} are not necessary for any arm of this statement
WARNING: braces {} are not necessary for single statement blocks
WARNING: printk() should include KERN_ facility level
WARNING: line over 80 characters
__func__ should be used instead of gcc specific __FUNCTION__
ERROR: that open brace { should be on the previous line
WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable

Signed-off-by: Xenofon Foukas <foukas.xenofon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>