USES=llvm:min=17 wants 17 when 19 is installed

The port lang/picolisp currently depends on LLVM 17. It works fine with 
newer versions of LLVM too, so in the process of updating it to a new 
version, I thought I'd update the llvm requirement.

I currently have llvm-19 installed, and I am trying to modify the USES 
line to be USES=llvm:min=17,lib in the port's Makefile.
I would expect the port to be happy with version 19, but apparently it 
wants 17:

$ pkg info -x llvm
llvm19-19.1.0.r4

$ grep USES Makefile
USES=           gmake llvm:min=17,lib pkgconfig readline ssl tar:tgz

# make all-depends-list | grep llvm
ports/devel/llvm17

Any idea?

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Pietro Cerutti
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