Merge branch 'libbpf-support-module-function-syntax-for-tracing-programs'

Viktor Malik says:

====================
libbpf: support "module:function" syntax for tracing programs

In some situations, it is useful to explicitly specify a kernel module
to search for a tracing program target (e.g. when a function of the same
name exists in multiple modules or in vmlinux).

This change enables that by allowing the "module:function" syntax for
the find_kernel_btf_id function. Thanks to this, the syntax can be used
both from a SEC macro (i.e. `SEC(fentry/module:function)`) and via the
bpf_program__set_attach_target API call.
---

Changes in v2:
- stylistic changes (suggested by Andrii)
- added Andrii's ack to the second patch
====================

Link: https://lore.kernel.org/r/cover.1714469650.git.vmalik@redhat.com
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>