Revert "Enable -Wfortify-source"

This reverts commit ca5e3eb4.

Reason for revert: falcon and seahawk build failures on git_main.
(cherry picked from https://android-review.googlesource.com/q/commit:32e35e416ecc8c297ed761bcd1e6cdcc96a76ac6)
Merged-In: Ib48e33dbb1649641223013739bb85934342a067a
Change-Id: Ib48e33dbb1649641223013739bb85934342a067a