sensor: lis2dh: Fix gcc8 compiler warning

We get the following warning with sdk-ng:

	drivers/sensor/lis2dh/lis2dh.c:210:38: error: bitwise comparison
	always evaluates to false [-Werror=tautological-compare]

	if ((value & LIS2DH_LP_EN_BIT_MASK) == 1 && ...
                                      ^~
The test needs to be:
	(value & LIS2DH_LP_EN_BIT_MASK) == LIS2DH_LP_EN_BIT_MASK

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>