[ports/lang/clover] Build with llvm90

[soralx at cydem.org]

Howdy!

 This is how to build clover with llvm90:
    vi +632 ./work/mesa-19.0.8/src/gallium/targets/opencl/Makefile
      Add -lclangASTMatchers to -lclangAnalysis

 I did not extensively test clover built with current llvm, but
 at least it compiles. Perhaps this can be made into an extra
 patch which applies if llvm90 is installed?

-- 
[SorAlx]  ridin' VN2000 Classic LT