fix: Print closure missing error message at compile time instead of run time. (#1781)

Prevent complications on the GPU by printing error messages at compile time instead of generating code to print them at runtime when a closure doesn't exist.

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Signed-off-by: Stephen Friedman <[email protected]>

Author: sfriedmapixar

src/liboslexec/llvm_gen.cpp

@@ -3830,11 +3830,11 @@ LLVMGEN(llvm_gen_closure)
     const ClosureRegistry::ClosureEntry* clentry
         = rop.shadingsys().find_closure(closure_name);
     if (!clentry) {
-        rop.llvm_gen_error(fmtformat(
+        rop.shadingcontext()->errorfmt(
             "Closure '{}' is not supported by the current renderer, called from {}:{} in shader \"{}\", layer {} \"{}\", group \"{}\"",
             closure_name, op.sourcefile(), op.sourceline(),
             rop.inst()->shadername(), rop.layer(), rop.inst()->layername(),
-            rop.group().name()));
+            rop.group().name());
         return false;
     }