The sdk and package-canonical targets were suffering from bit rot.
Unbreak. [1]

The port build fails with gcc 4.9, convert to USE_GCC=4.8. [2]

Differential Revision: https://reviews.freebsd.org/D1557
Submitted by: pfg [1]
Submitted by: gerald [2]
Reviewed by: pfg
Approved by: mat (mentor)