drm/i915: Fix whitespace issues

Fix the poorly indented port parameters to the aux ctl and data
reg functions. This was fallout from the s/i915_mmio_reg_t/i915_reg_t/
that happened during the review of commit f0f59a00

 ("drm/i915:
Type safe register read/write")

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476208368-5710-5-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>