Fix linker errors "relocation R_X86_64_32 against .rodata"

Fix linker errors "relocation R_X86_64_32 against .rodata"

... "can not be used when making a shared object; recompile with -fPIC"

Caused by some libraries built without libtool in certain environments.
NP: there are other libraries in Squid built without libtool but they
    appear not to be having these linker issues at this time.

Also, fixes "undefined symbol eui64_aton" uncovered by these changes.