drm/i915/cnl: Remove useless conversion.

No functional change. Just starting the wrpll fixes
with a clean-up to make units a bit more clear.

Cc: Mika Kahola <mika.kahola@intel.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: James Ausmus <james.ausmus@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171114194759.24541-3-rodrigo.vivi@intel.com

drivers/gpu/drm/i915/intel_dpll_mgr.c

@@ -2198,11 +2198,11 @@ static void cnl_wrpll_params_populate(struct skl_wrpll_params *params, uint32_t
 }
 
 static bool
-cnl_ddi_calculate_wrpll(int clock /* in Hz */,
+cnl_ddi_calculate_wrpll(int clock,
 			struct drm_i915_private *dev_priv,
 			struct skl_wrpll_params *wrpll_params)
 {
-	uint64_t afe_clock = clock * 5 / KHz(1); /* clocks in kHz */
+	uint64_t afe_clock = clock * 5;
 	unsigned int dco_min = 7998 * KHz(1);
 	unsigned int dco_max = 10000 * KHz(1);
 	unsigned int dco_mid = (dco_min + dco_max) / 2;
@@ -2255,7 +2255,7 @@ static bool cnl_ddi_hdmi_pll_dividers(struct intel_crtc *crtc,
 
 	cfgcr0 = DPLL_CFGCR0_HDMI_MODE;
 
-	if (!cnl_ddi_calculate_wrpll(clock * 1000, dev_priv, &wrpll_params))
+	if (!cnl_ddi_calculate_wrpll(clock, dev_priv, &wrpll_params))
 		return false;
 
 	cfgcr0 |= DPLL_CFGCR0_DCO_FRACTION(wrpll_params.dco_fraction) |