Fix Makefile in runtime to create proper /pkg subdir.
Fix Makefile in runtime to create proper /pkg subdir.

R=rsc
APPROVED=rsc
DELTA=2  (1 added, 0 deleted, 1 changed)
OCL=30043
CL=30043
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go