Add new OpenPGP signing key
`0D23D34C577B08C4082CFD76430C5CFF993116B1`, which is signed by the
previous (`38A644698C69787344E954CE29EE848AE2CCF3F4`).
Switch to signed git tags as more transparent sources.
Rely on the `sig-libcap-<version>` tagging scheme, which features
signatures done with the newly added OpenPGP key.

Related upstream issue on release signing:
https://bugzilla.kernel.org/show_bug.cgi?id=218860

Add license file.
Add versioned dependency on libcap in package() as in global depends
it would break the build (a dependency cycle with lib32-pam ->
lib32-systemd -> lib32-libcap pulls in the previous version of libcap).

Signed-off-by: David Runge <dvzrv@archlinux.org>

Signed-off-by: David Runge <dvzrv@archlinux.org>

Use bash arrays with one entry per line for better handling.
Move make options to local bash arrays for better handling.

devtools 20230105-1 enables the debug option by default.

A follow-up commit will remove debug from alongside other options.

Remove unneeded quotes and curly braces.
Add debug package.

Add lib32-gcc-libs as additional dependency.
Simplify make calls.
Remove unneeded prepare().

Simplify quoting in file.
Add info on removal of files.

Drop all patches as upstream has included them.

As the fix for the executable pam module broke the use of LDFLAGS, add those
back.
Rework the use of CPPFLAGS and circumvention of hardcoding sbin, as those have
also been broken by the recent release.

Add fix for tests with pam_cap.so by explicitly linking against libpam.so:
https://bugzilla.kernel.org/show_bug.cgi?id=214023

Also set CC for test target in check().

Sync PKGBUILD with core/libcap.
Depend on the same version of core/libcap.
Add lib32-pam to depends (for pam integration).