10804 Enable unused warnings outside of uts
Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Reviewed by: Toomas Soome <tsoome@me.com>

@@ -90,10 +90,11 @@
 CERRWARN += -_gcc=-Wno-parentheses
 CERRWARN += -_gcc=-Wno-uninitialized
 CERRWARN += -_gcc=-Wno-switch
 CERRWARN += -_gcc=-Wno-char-subscripts
 CERRWARN += -_gcc=-Wno-type-limits
+$(RELEASE_BUILD)CERRWARN += -_gcc=-Wno-unused
 
 SMOFF += no_if_block
 
 # Location of the shared relocation engines maintained under usr/src/uts.
 #