Revert "BACKPORT: FROMGIT: userfaultfd/selftests: add test exercising minor fault handling"

This reverts commit 2b2f7d6a04d65c2ebd53f9e5d3de6b55635d57b6 so that it
can be re-applied once dependcies are brought in.

Signed-off-by: Lokesh Gidra <lokeshgidra@google.com>
Bug: 187930641
Change-Id: Ib24c94e1d8ec6c46004d35f58e48d9d35eeb8312