Auto merge of #2446 - glennw:bump-x11-dl, r=mrobinson

Update x11-dl version.

As of this morning, I am seeing XCB SIGILL crashes whenever I
try to load wrench in release mode.

Updating x11-dl appears to fix this. The commit notes between
the version we're using and the current version include a few
references to undefined behaviour, and incorrect bindings, so
it seems reasonable that this fixes the crash.

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