devel/ccls: unbreak with DEFAULT_VERSIONS+=llvm=-devel
Don't try hard to make LIB_DEPENDS pick the specific version when this
is already enforced by BUILD_DEPENDS. The left field in _DEPENDS lines
isn't recorded into binary packages, anyway.
=======================<phase: lib-depends >============================
===> ccls-0.20190301_2 depends on shared library: libLLVM--devel.so - not found
===> Installing existing package /packages/All/llvm-devel-9.0.d20190226.txz
[120i386-default-llvm90-job-07] Installing llvm-devel-9.0.d20190226...
the most recent version of llvm-devel-9.0.d20190226 is already installed
===> ccls-0.20190301_2 depends on shared library: libLLVM--devel.so - not found
*** Error code 1
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