Add irt_random to szbuild link line.

Add irt_random to szbuild link line.

Seems to be part of the non-sfi link now:
https://codereview.chromium.org/686723003/diff/180001/pnacl/driver/pnacl-translate.py

Otherwise I get:
x86-32-linux/lib/unsandboxed_irt.o:(.rodata+0x68): undefined reference to `nacl_secure_random'

BUG=none
R=stichnot@chromium.org

Committed: https://gerrit.chromium.org/gerrit/gitweb?p=native_client/pnacl-subzero.git;a=commit;h=edc115ec12829b3daea95ecad4a49f72e1de5666

[jvoung (off chromium), 2014-11-14 21:27:46]

jvoung@chromium.org changed reviewers:
+ kschimpf@chromium.org, stichnot@chromium.org

[Jim Stichnoth, 2014-11-14 21:30:18]

lgtm

[jvoung (off chromium), 2014-11-14 21:50:01]

Committed patchset #1 (id:1) manually as
edc115ec12829b3daea95ecad4a49f72e1de5666 (tree was closed).