Merge branch 'libbpf: uprobe name-based attach followups'

Alan Maguire says:

====================

Follow-up series to [1] to address some suggestions from Andrii to
improve parsing and make it more robust (patches 1, 2) and to improve
validation of u[ret]probe firing by validating expected argument
and return values (patch 3).

[1] https://lore.kernel.org/bpf/164903521182.13106.12656654142629368774.git-patchwork-notify@kernel.org/

Changes since v1:
- split library name, auto-attach parsing into separate patches (Andrii, patches 1, 2)
- made str_has_sfx() static inline, avoided repeated strlen()s by storing lengths,
  used strlen() instead of strnlen() (Andrii, patch 1)
- fixed sscanf() arg to use %li, switched logging to use "prog '%s'" format,
  used direct strcmp() on probe_type instead of prefix check (Andrii, patch 2)
- switched auto-attach tests to log parameter/return values to be checked by
  user-space side of tests. Needed to add pid filtering to avoid capturing
  stray malloc()s (Andrii, patch 3)
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>