Patch 7.4.208 updated by upstream

Note: This patch was made empty, because .hgignore is not part of the
distributed files.
updated to 7.4.258

7.4.254  smack support detection is incomplete
7.4.255  configure check for smack doesn't work with all shells
7.4.256  (after 7.4.248) systemlist() does not work properly
7.4.257  compiler warning, possibly for mismatch in parameter name
7.4.258  configure fails if $CC contains options