Dear Maintainer,

I am trying to compile the shipped examples and gcc fails with:

gcc /usr/share/doc/libpfm4-dev/examples/showevtinfo.c -o showevtinfo -lpfm
/usr/share/doc/libpfm4-dev/examples/showevtinfo.c:36:10: fatal error: perfmon/err.h: No such file or directory
   36 | #include <perfmon/err.h>
      |          ^~~~~~~~~~~~~~~

gcc /usr/share/doc/libpfm4-dev/examples/check_events.c -o check_events -lpfm
/usr/share/doc/libpfm4-dev/examples/check_events.c:33:10: fatal error: perfmon/err.h: No such file or directory
   33 | #include <perfmon/err.h>
      |          ^~~~~~~~~~~~~~~

so /usr/include/perfmon/err.h got lost somewhere during packaging, it is still in upstream:
https://sourceforge.net/p/perfmon2/libpfm4/ci/master/tree/include/perfmon/err.h

Best regards,
Marius