updated _ssh_or_mosh_args() (2), fixes gpakosz#627

do not try to ignore the command if supplied

parsing the ssh command line is brittle and people sometimes pass
options after user@hostname, e.g.

ssh -p 222 user@hostname -I /usr/lib/x86_64-linux-gnu/pkcs11/opensc-pkcs11.so

.tmux.conf

@@ -531,7 +531,7 @@ run 'cut -c3- ~/.tmux.conf | sh -s _apply_configuration'
 # _ssh_or_mosh_args() {
 #   case "$1" in
 #     *ssh*)
-#       args=$(printf '%s' "$1" | perl -n -e 'print if s/.*?\bssh[\w]*\s*((?:\s+-\w+)*)(\s+\w+)(\s\w+)?/\1\2/')
+#       args=$(printf '%s' "$1" | perl -n -e 'print if s/.*?\bssh[\w_-]*\s*(.*)/\1/')
 #       ;;
 #     *mosh-client*)
 #       args=$(printf '%s' "$1" | sed -E -e 's/.*mosh-client -# (.*)\|.*$/\1/' -e 's/-[^ ]*//g' -e 's/\d:\d//g')