Bionic and maybe some other libc implementations lack the _r nss functions.
This replaces our current getpwnam_r and getpwuid_r calls by getpwnam and
getpwuid.
Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>