[flang] Fix another crash from another fuzzer test. (#122562)

Fixes https://github.com/llvm/llvm-project/issues/122045.

flang/test/Semantics/bug122045.f90

@@ -0,0 +1,6 @@
+! RUN: %python %S/test_errors.py %s %flang_fc1
+! ERROR: Must be a scalar value, but is a rank-1 array
+! ERROR: Shape of initialized object 'a' must be constant
+complex:: a(n) = SUM([1])
+INTEGER, parameter :: n(2) = [2,2]
+end