prospero-pkg-config broken with pkgconf 3.x

[rootlis]

When pkgconf 3.x provides pkg-config, prospero-pkg-config returns target paths without the SDK sysroot prepended, causing build failures.

For example, when using pkgconf 3.0.6 with freetype installed from pacbrew-repo:

$ source /opt/ps5-payload-sdk/toolchain/prospero.sh
$ $PKG_CONFIG --cflags freetype2
-I/user/homebrew/include/freetype2 -I/user/homebrew/include/libpng16 -I/user/homebrew/include

Pkgconf 2.5.1 correctly includes the sysroot:

$ $PKG_CONFIG --cflags freetype2
-I/opt/ps5-payload-sdk/target/user/homebrew/include/freetype2 -I/opt/ps5-payload-sdk/target/user/homebrew/include/libpng16 -I/opt/ps5-payload-sdk/target/user/homebrew/include

This issue may be related to new pkgconf 3.x behavior where sysroot injection is disabled if DESTDIR is the same as PKG_CONFIG_SYSROOT_DIR. Unsetting DESTDIR before testing with pkgconf 3.0.6 restores the expected output:

$ env -u DESTDIR $PKG_CONFIG --cflags freetype2
-I/opt/ps5-payload-sdk/target/user/homebrew/include/freetype2 -I/opt/ps5-payload-sdk/target/user/homebrew/include/libpng16 -I/opt/ps5-payload-sdk/target/user/homebrew/include

[john-tornblom]

Thanks, will look into it when I get some time