/usr/lib/x86_64-linux-gnu/pkgconfig/libgit2.pc is in libgit2-dev 0.19.0-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 | libdir=/usr/lib/x86_64-linux-gnu
includedir=/usr/include
Name: libgit2
Description: The git library, take 2
Version: 0.19.0
Requires: libcrypto
Libs: -L${libdir} -lgit2 -lz -lcrypto
Cflags: -I${includedir}
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