It is used because it is in FC2. I believe it is in recent SuSe too. I think it is requred for x86_64.
I changed it to be configurable in the Makefile. Just enter your libpci version there and it will compile. Unfortunately there is no simple way
I didn't see that in V2 makefile I was using. All it had was a hardcoded path /usr/lib/libpci.a
Both the #include statements in the .c files and the path to the library had to be changed.