[Flang] [OpenMP] [Semantics] Change SIMD ALIGNED clause support from parsing a...

[Flang] [OpenMP] [Semantics] Change SIMD ALIGNED clause support from parsing a std::list<Name> to OmpObjectlist

This is an assisting patch which is implemented to address review comment to switch std::list<Name> to OmpObjectlist from https://reviews.llvm.org/D142722.

Also addressed a semantic check https://github.com/llvm/llvm-project/issues/61161 OpenMP 5.2 standard states that only pointer variables (C_PTR, Cray pointers, POINTER or ALLOCATABLE items) can appear in SIMD aligned clause (section 5.11). And not to allow common block names on an ALIGNED clause.

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D152637