pkgconfig: Remove unneeded Requires.private
Fixes "pkg-config --exists xkbcomp" without installed pkg-config files for x11, xkbfile, and xproto >= 7.0.17.
xkbcomp works fine without those pkg-config files.
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Fixes "pkg-config --exists xkbcomp" without installed pkg-config files for x11, xkbfile, and xproto >= 7.0.17.
xkbcomp works fine without those pkg-config files.