drm/i915: Drop the definite article in front of SAGV

drm/i915: Drop the definite article in front of SAGV

The spec doesn't use a definite article in front of SAGV. The
rules regarding articles and initialisms are super fuzzy, but
at least to my ears it sounds much more natural to not have
the article. Perhaps because I tend to pronounce it as
"sag-vee" instead of spelling out the letters one at a time.
Actually I might still prefer to leave out the article if I
did spell them out.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181221171436.8218-8-ville.syrjala@linux.intel.com
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>