drm/i915/fbc: Reduce fbc1 compression interval to 1 second

drm/i915/fbc: Reduce fbc1 compression interval to 1 second

The default fbc1 compression interval we use is 500 frames. That
translates to over 8 seconds typically. That's rather excessive
so let's drop it to 1 second.

The hardware will not attempt recompression unless at least one
line has been modified, so a shorter compression interval should
not cause extra bandwidth use in the purely idle scenario. Of
course in the mostly idle case we are possibly going to recompress
a bit more.

Should really try to find some kind of sweet spot to minimize
the energy usage...

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-11-ville.syrjala@linux.intel.com
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>