Zhigang Gong authored Nov 09, 2011 and Emma Anholt committed Dec 18, 2013

For the purpose of incrementally intergration of existing intel
driver, for the GC operations we may don't want to use glamor's
internal fallback which is in general much slower than the
implementation in intel driver. If the parameter "fallback" is
false when call the glamor_fillspans, then if glamor found it
can't accelerate it then it will just return a FALSE rather than
fallback to a slow path.

Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>