linux pr testing is broken

Hi Danial,

Looks like your recent merge in libdispatch broke the linux PR bot:

https://ci.swift.org/job/swift-PR-Linux-smoke-test/5126/

/home/buildnode/jenkins/workspace/swift-PR-Linux-smoke-test/branch-master/buildbot_linux/libdispatch-linux-x86_64/tests/dispatch/source_private.h:81:33: error: expected parameter declarator
API_DEPRECATED_WITH_REPLACEMENT("DISPATCH_SOURCE_TYPE_MEMORYPRESSURE",
                                ^
/home/buildnode/jenkins/workspace/swift-PR-Linux-smoke-test/branch-master/buildbot_linux/libdispatch-linux-x86_64/tests/dispatch/source_private.h:81:33: error: expected ')'

Can you please fix or revert?

Thanks,
Erik