[flang] Fix CHECK() calls on erroneous procedure declarations

When writing tests for a previous problem, I ran across situations where the
compiler was failing calls to CHECK().  In these situations, the compiler had
inconsistent semantic information because the programs were erroneous.  This
inconsistent information was causing the calls to CHECK().

I fixed this by avoiding the code that ended up making the failed calls to
CHECK() and making sure that we were only avoiding these situations when the
associated symbols were erroneous.

I also added tests that would cause the calls to CHECK() without these changes.

Differential Revision: https://reviews.llvm.org/D99342