Changes from 1.9.2 to 1.9.3:
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* Fix a bunch of minor code issues pointed out using Clang static analyzer.
* New API: pkgconf_solution_free(), which frees a compiled solution graph.
* Fix behavior when overriding global variables with '--define-variable'.
Signed-off-by: Wang Mingyu <wangmy@fujitsu.com> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>