Log Message:
pkgconf: update to 1.7.3.

Changes from 1.7.2 to 1.7.3:
----------------------------

* Bug fixes:
  - Fix a possible out of boundary write when evaluating dependencies.
    Patch by Tobias Stöckmann.
  - Fix escaping logic on Windows.  Patch by Vincent Torri.
  - Fix out of boundary reads and writes with a malformed fragment.
    Patches by Tobias Stöckmann.
  - Fix a possible out of boundary write when evaluating tuples.
    Patch by Tobias Stöckmann.

Changes from 1.7.1 to 1.7.2:
----------------------------

* Bug fixes:
  - Fix a windows-specific crash relating to path fixups.

Changes from 1.7.0 to 1.7.1:
----------------------------

* Bug fixes:
  - Fix a possible out of boundary access in the parser for the
    cross-compile database.  Patch by Tobias Stöckmann.
  - Missing files for building with Meson are now included in the
    tarball.  Patch by Neal Gompa.
  - Fix calculation of package atoms on Windows with paths that
    use both directory separator characters.

Changes from 1.6.3 to 1.7.0:
----------------------------

* Bug fixes:
  - Fix a possible buffer overflow involving newline escaping.
    Patch by Tobias Stöckmann.
  - Fix an out of boundary access in the parser.
    Patch by Tobias Stöckmann.
  - Fix leakage of strcmp() result value in pkgconf_compare_version()
    responses.
  - Return the default personality if loading a cross-compile
    personality file failed.
  - Do not complain about newlines when validating package versions.
  - Properly detect strndup() on Windows when building with Meson.

* Enhancements:
  - A new --shared option and WantDefaultStatic cross-compile
    configuration option have been added.  This allows for toolchains
    to specify that static linking should be used by default.
  - Support for the PKG_CONFIG_MSVC_SYNTAX environment variable has
    been added.  Patch by Dan Kegel.
  - Support for the PKGCONF_PKG_PKGF_DONT_MERGE_SPECIAL_FRAGMENTS
    client flag which disables emulation of freedesktop.org pkg-config
    fragment merging semantics has been added.
    Patch by Karen Arutyunov.

Changes from 1.6.2 to 1.6.3:
----------------------------

* Bug fixes:
  - Properly tokenize versions.  Versions cannot logically contain
    whitespace, as dependency-lists would not properly tokenize if
    they could.  A diagnostic is generated for malformed version
    strings containing whitespace when --validate is used.

* Enhancements:
  - CMake support has been dropped.  Use Meson to build on Windows.

Changes from 1.6.1 to 1.6.2:
----------------------------

* Bug fixes:
  - Fixed a memory leak when deduplicating paths.
  - Fixed strndup-related build regression on Windows.

* Enhancements:
  - Added pkgconf-lite variant.  pkgconf-lite is a stripped down
    variant of pkgconf that only includes pkg-config features.
  - Added --modversion description to pkgconf(1) man page.