Fix frame pointer alignment check.
Fix frame pointer alignment check.

The frame pointer sanity check in NextStackFrame() was more restrictive than it is necessary. The frame pointer is used to load the saved link-register and the address for the next stack frame. So it only needs to be 8-byte aligned. The aarch64 ABI does not specify an alignment requirement for the frame point.

PiperOrigin-RevId: 463368519
Change-Id: I473e05181603288f14734fe29013900c7505e201

abseil/abseil-cpp,abseil/abseil-cpp,abseil/abseil-cpp,abseil/abseil-cpp