[Sanitizer] Add new flag -sanitize-stable-abi flag to link against the #1509
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new sanitiers stable ABI in compiler-rt.
Compiler-rt recently introduced a stable ABI for sanitizers. This patch adds a flag to pass this flag to swift-frontend during compilation and clang at link time to link against the new stable ABI.
NOTE: this was #1495 , but Usama is out till after the new year break, so I need to take over and apply feedback from there
rdar://118997873