Only override sysconfdir and mandir when prefix=/usr

(closes issue #13093)
 Reported by: pabelanger


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@134536 65c4cc65-6c06-0410-ace0-fbb531ad65f3

configure.ac

@@ -28,11 +28,13 @@ case "${host_os}" in
      ;;
      *)
      ac_default_prefix=/usr
-     if test ${sysconfdir} = '${prefix}/etc'; then
-        sysconfdir=/etc
-     fi
-     if test ${mandir} = '${prefix}/man'; then
-        mandir=/usr/share/man
+     if test ${prefix} = '/usr'; then
+        if test ${sysconfdir} = '${prefix}/etc'; then
+           sysconfdir=/etc
+        fi
+        if test ${mandir} = '${prefix}/man'; then
+           mandir=/usr/share/man
+        fi
      fi
      ;;
 esac