[flang][OpenMP] Allow default(none) to access variables with PARAMETER attribute

This patch fixes https://github.com/flang-compiler/f18-llvm-project/issues/1351.
Concretely, data-sharing attributes on PARAMETER data used in a block
with DEFAULT(NONE) should be ignored.

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D129444