[AddressSanitizer] Add fallback DebugLocation for instrumented calls
When building the kernel with LTO, KASAN & debug information enabled,
multiple inlinable AddressSanitizer functions require debug information
present.
In such cases we repurpose the InstrumentationIRBuilder that ensures
the necessary debug information is added if necessary.
This has been done analogous to the work for the ThreadSanitizer
in D124937.
Bug: https://github.com/ClangBuiltLinux/linux/issues/1721
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D155376