[AArch64] Add native CPU detection for Neoverse-V1.

Map Main ID part number 0xd40 to neoverse-v1, as described in the
Neoverse-V1 Technical Reference Manual:

https://developer.arm.com/documentation/101427/0101/Register-descriptions/AArch64-system-registers/MIDR-EL1--Main-ID-Register--EL1

Differential Revision: https://reviews.llvm.org/D117207