ACPI: LPSS: Fix the fractional clock divider flags

The conversion to CLK_FRAC_DIVIDER_POWER_OF_TWO_PS uses wrong flags
in the parameters and hence miscalculates the values in the clock
divider. Fix this by applying the flag to the proper parameter.

Fixes: 82f53f9e

 ("clk: fractional-divider: Introduce POWER_OF_TWO_PS flag")
Reported-by: Alex Vinarskis <alex.vinarskis@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>