Tweak the OnePass versus DFA cutoff.

According to benchmark results from running on Skylake machines,
DFA doesn't clearly overtake OnePass until more like 16 bytes...

Change-Id: Ic8c8dd28545ba35b358df5e8105e58aae1d42008
Reviewed-on: https://code-review.googlesource.com/c/re2/+/59170
Reviewed-by: Paul Wankadia <junyer@google.com>
1 file changed