build: Bump pkg-config from 0.3.25 to 0.3.26

Bumps [pkg-config](https://github.com/rust-lang/pkg-config-rs) from 0.3.25 to 0.3.26.
- [Release notes](https://github.com/rust-lang/pkg-config-rs/releases)
- [Changelog](https://github.com/rust-lang/pkg-config-rs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-lang/pkg-config-rs/compare/0.3.25...0.3.26)

---
updated-dependencies:
- dependency-name: pkg-config
  dependency-type: indirect
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.lock

@@ -759,9 +759,9 @@ dependencies = [
 
 [[package]]
 name = "pkg-config"
-version = "0.3.25"
+version = "0.3.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1df8c4ec4b0627e53bdf214615ad287367e482558cf84b109250b37464dc03ae"
+checksum = "6ac9a59f73473f1b8d852421e59e64809f025994837ef743615c6d0c5b305160"
 
 [[package]]
 name = "pnet"