[Makefile] Changed to -O2 in pin/Makefile
[Makefile] Changed to -O2 in pin/Makefile

fhijaz/Graphite,fhijaz/Graphite,victorisildur/Graphite,mit-carbon/Graphite-Cycle-Level,nkawahara/Graphite,mit-carbon/Graphite-Cycle-Level,8l/Graphite,mit-carbon/Graphite-Cycle-Level,victorisildur/Graphite,fhijaz/Graphite,fhijaz/Graphite,8l/Graphite,8l/Graphite,mit-carbon/Graphite-Cycle-Level,nkawahara/Graphite,nkawahara/Graphite,mit-carbon/Graphite,nkawahara/Graphite,victorisildur/Graphite,victorisildur/Graphite,8l/Graphite,mit-carbon/Graphite,mit-carbon/Graphite,mit-carbon/Graphite