Only use -fPIC for the shared library
Only use -fPIC for the shared library

We don't need it on the static side, and for some reason we were left
in a weird state where we used -shared -fPIC on the shared object file,
but just -fPIC on the static library.

Signed-off-by: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@kernel.dk>

axboe/liburing,axboe/liburing,axboe/liburing