WebKitGTK+ 2.11.5 will no longer depend on LLVM

[Michael Catanzaro <mcatanzaro gnome org>]

Hi distributors,

Many of you have already adapted your WebKitGTK+ packages after
noticing that we recently added a dependency on LLVM as part of
significant performance improvements to the JavaScriptCore engine
(enabling the fourth-tier LLVM or faster-than-light JIT, aka FTL JIT).

For the next release, the LLVM dependency is no longer needed as we now
have a faster FTL backend (bare-bones backend, B3). You will be able to
remove it as a build dependency in your package build system.

Michael