Revert "Clarify that a leak is negligible at h2o_hpack_decode_header"
Revert "Clarify that a leak is negligible at h2o_hpack_decode_header"

This reverts commit f0d62e2dcf4133b1505eec0cc8523b18e3bf1dbb.

h2o/h2o,devnexen/h2o,cwyang/h2o,yannick/h2o,h2o/h2o,yannick/h2o,devnexen/h2o,yannick/h2o,h2o/h2o,yannick/h2o,cwyang/h2o,devnexen/h2o,yannick/h2o,devnexen/h2o,h2o/h2o,h2o/h2o,cwyang/h2o,devnexen/h2o,yannick/h2o,h2o/h2o,yannick/h2o,devnexen/h2o,devnexen/h2o,h2o/h2o,devnexen/h2o,yannick/h2o,cwyang/h2o,devnexen/h2o,cwyang/h2o,cwyang/h2o,yannick/h2o,h2o/h2o,cwyang/h2o,h2o/h2o,cwyang/h2o