staging: comedi: drivers: pcl812.c: add curly braces for checkpatch

Kernel style is that if one side of the if else statement gets has curly
braces then both side should have them.

Signed-off-by: Kumar Amit Mehta <gmate.amit@gmail.com>
Acked-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>