Recognize all NetBSD architectures in UBSan

Summary:
Use uniform accessors for Program Pointer,
Stack Pointer and Frame Pointer.

Remove CPU check in UBSan supported platforms
and rely only on the OS type.

This adds NetBSD support in GetPcSpBp() for:
 - ARM
 - ARM64
 - HPPA
 - PowerPC/PowerPC64
 - SPARC/SPARC64
 - MIPS
 - DEC Alpha AXP
 - DEC VAX
 - M68K and M68010
 - SH3
 - IA64
 - OR1K
 - RISCV

Sponsored by <The NetBSD Foundation>

Reviewers: joerg, vitalybuka, ro

Reviewed By: vitalybuka

Subscribers: aemerson, jyknight, sdardis, kubamracek, arichardson, llvm-commits, kristof.beyls, fedor.sergeev, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D43021

llvm-svn: 325431