dwarves: support DW_TAG_atomic_type

Throwing userspace programs with atomic types at pahole currently
results in either odd results (struct fiels with zero length) or
straight up segfaults (dereferencing a NULL tag).

Add DW_TAG_atomic_type analogous to DW_TAG_volatile_type (which it
behaves identically to.)

Committer notes:

Define DW_TAG_atomic_type to get this to build in older systems.

Signed-off-by: David Lamparter <equinox@diac24.net>
5 files changed