Revert "Don't trate unused-parameter warnings as errors"

This reverts commit 05ab057b50aca1d090e0fcdaa41b451936cb372b.
Revert "Typo"

This reverts commit ef384b960c7aec3cfb69eec3717292ac0a57fb5f.
Revert "Don't trate unused-parameter warnings as errors"

This reverts commit 879a5ab8f4c8af31d7607e477cbf244623d82f86.
Revert "Enable -O2 optimizations"

This reverts commit 0ce6d2c650f84ccbe10cafa3cdd31da672e33fd9.

Conflicts:
	core/combo/TARGET_linux-arm.mk