Remove unnecessary check of line number

Apparently the debug info can still be useful even when the line number is invalid (i.e. function name).

Curretly this seems to occur with callback in single line comprehensions.

Author: yuyichao

src/codegen.cpp

@@ -8936,8 +8936,6 @@ static jl_llvm_functions_t
                     func = debuginfo->def; // this is inlined
                 struct jl_codeloc_t lineidx = jl_uncompress1_codeloc(debuginfo->codelocs, pc);
                 size_t i = lineidx.line;
-                if (i < 0) // pc out of range: broken debuginfo?
-                    return false;
                 if (i == 0 && lineidx.to == 0) // no update
                     return false;
                 if (pc > 0 && (jl_value_t*)debuginfo->linetable != jl_nothing) {