libselinux: Fix cross-compilation

[jwillikers]

Apply patches for 3.6 to fix detection of available functions when cross-compiling. Use the PKG_CONFIG_LIBDIR to point pkg-config to the correct directory containing Conan's generated pkg-config files. Without this, the pcre2 from the system will be picked up before the one provided by Conan. When cross-compiling, this causes system include directories to poison the build.

libselinux-3.6-cross-fixed-log.txt
libselinux-3.6-cross-broken-log.txt

[franramirez688]

Hi @jwillikers Thanks a lot for this PR (and the associated issue 😁 )

Sorry for the huge delay! I'm just revisiting all my old assigned issues! 🙏

LGTM! I only have a question regarding to the environment.

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 5 (785e1fa6a12e4a4e666555b07f5a7f7caee3c0ec):

• libselinux/3.6:
  All packages built successfully! (All logs)

• libselinux/3.5:
  All packages built successfully! (All logs)

• libselinux/3.1:
  All packages built successfully! (All logs)

• libselinux/3.3:
  All packages built successfully! (All logs)

• libselinux/3.2:
  All packages built successfully! (All logs)

• libselinux/3.0:
  All packages built successfully! (All logs)

• libselinux/2.9:
  All packages built successfully! (All logs)

---

Conan v2 pipeline ✔️

Note: Conan v2 builds are now mandatory. Please read our discussion about it.

All green in build 5 (785e1fa6a12e4a4e666555b07f5a7f7caee3c0ec):

• libselinux/3.6:
  All packages built successfully! (All logs)

• libselinux/3.5:
  All packages built successfully! (All logs)

• libselinux/3.2:
  All packages built successfully! (All logs)

• libselinux/3.3:
  All packages built successfully! (All logs)

• libselinux/3.1:
  All packages built successfully! (All logs)

• libselinux/3.0:
  All packages built successfully! (All logs)

• libselinux/2.9:
  All packages built successfully! (All logs)

[uilianries]

LGTM