staging: fbtft: ternary statement to if statement.

Convert a ternary statement into a if statement which is detected while
resolving "WARNING: line over 80 characters". Use BIT() macro instead
manually left shifting.

Signed-off-by: Bhagyashri Dighole <digholebhagyashri@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>