glib: Add missing pkg_config_names for PkgConfigDeps generator

[jwillikers]

Specify library name and version: glib/*

Dependencies like gst-plugins-base can't find gio-unix-2.0 when using the PkgConfigDeps generator because it is currently named incorrectly as glib-gio-unix-2.0.

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• I've read the guidelines for contributing.
• I've followed the PEP8 style guides for Python code in the recipes.
• I've used the latest Conan client version.
• I've tried at least one configuration locally with the conan-center hook activated.

[ghost]

I detected other pull requests that are modifying glib/all recipe:

• glib: several fixes & improvements #13440
• glib: bump libffi #13439
• glib: Fix test package to allow cross-compilation #13347
• glib: conan v2 support #12221

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[conan-center-bot]

All green in build 2 (562bafa48ae03c240861e18cc58da1aee71acd8a):

• glib/2.69.3@:
  All packages built successfully! (All logs)

• glib/2.68.3@:
  All packages built successfully! (All logs)

• glib/2.72.1@:
  All packages built successfully! (All logs)

• glib/2.70.4@:
  All packages built successfully! (All logs)

• glib/2.73.0@:
  All packages built successfully! (All logs)

• glib/2.71.3@:
  All packages built successfully! (All logs)

• glib/2.73.1@:
  All packages built successfully! (All logs)

• glib/2.73.3@:
  All packages built successfully! (All logs)

• glib/2.73.2@:
  All packages built successfully! (All logs)

• glib/2.74.0@:
  All packages built successfully! (All logs)