Staging: comedi: Prefer using the BIT macro

Replace all instances of bit shifting on 1 with the BIT(x) macro. In
addition, convert other non-1 shift operations with the equivalent
BIT(x) macro for uniformity. Issue pointed out by checkpatch.

CHECK: Prefer using the BIT macro

Signed-off-by: Aybuke Ozdemir <aybuke.147@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>