Snippets for acct 6.6.4 from Alpine s390x

Sourced from https://build.alpinelinux.org/buildlogs/build-edge-s390x/main/acct/acct-6.6.4-r2.log.

• readutmp.c:50:47: warning: argument to 'sizeof' in 'strncpy' call is the same expression as the source; did you mean to use the size of the destination? [-Wsizeof-pointer-memaccess]
     50 |   strncpy (trimmed_name, UT_USER (ut), sizeof (UT_USER (ut)));
        |                                               ^