We need libpmem 1.10 and Centos 9 Stream has it. On top of sticking
to distro-provided packages being generally a good thing, this fixes
a build failure: libpmem 1.10 doesn't build with LTO which is enabled
by default in Centos 9 Stream. The distro package works around it.
libpmem 1.10 is also there in Fedora 34 and Fedora 35.