- fix requested LLVM version

--- CMakeLists.txt.orig	2023-09-27 17:00:43 UTC
+++ CMakeLists.txt
@@ -413,7 +413,7 @@ set(WITH_LLVM no
 
 if (WITH_LLVM)
     set(SYMENGINE_LLVM_COMPONENTS asmparser core executionengine instcombine mcjit native nativecodegen scalaropts vectorize support transformutils passes)
-    find_package(LLVM REQUIRED ${SYMENGINE_LLVM_COMPONENTS})
+    find_package(LLVM ${FREEBSD_LLVM_VERSION} REQUIRED ${SYMENGINE_LLVM_COMPONENTS})
     set(LLVM_MINIMUM_REQUIRED_VERSION "4.0")
     if (LLVM_PACKAGE_VERSION LESS ${LLVM_MINIMUM_REQUIRED_VERSION})
 	    message(FATAL_ERROR "LLVM version found ${LLVM_PACKAGE_VERSION} is too old.