powercap/drivers/dtpm: Fix a double shift bug

powercap/drivers/dtpm: Fix a double shift bug

The DTPM_POWER_LIMIT_FLAG is used for test_bit() etc which take a bit
number so it should be bit 0.  But currently it's set to BIT(0) then
that is double shifted equivalent to BIT(BIT(0)).  This doesn't cause a
run time problem because it's done consistently.

Fixes: a20d0ef97abf ("powercap/drivers/dtpm: Add API for dynamic thermal power management")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>