Remove global -Wno-stringop-overflow, -Wno-stringop-overread compiler…

… options (facebookincubator#9432)

Summary:
This PR makes a change to remove the globally applied `-Wno-stringop-overflow` and `-Wno-stringop-overread` compiler options for GNU to warn for buffer overflows and undefined behaviour from reading past the end of the source buffer. PR facebookincubator#4618 originally disabled it.

Meant to address facebookincubator#9469

Pull Request resolved: facebookincubator#9432

Reviewed By: Yuhta

Differential Revision: D56193789

Pulled By: pedroerp

fbshipit-source-id: b25bd8df8bfba1fd7f5205e7e4976ac10455206d

CMakeLists.txt

@@ -340,9 +340,7 @@ if("${ENABLE_ALL_WARNINGS}")
          -Wno-unused-result \
          -Wno-format-overflow \
          -Wno-strict-aliasing \
-         -Wno-type-limits \
-         -Wno-stringop-overflow \
-         -Wno-stringop-overread")
+         -Wno-type-limits")
   endif()
 
   set(KNOWN_WARNINGS