[bash/zsh] Take SSH completion hints from known_hosts

Signed-off-by: Junegunn Choi <junegunn.c@gmail.com>

shell/completion.bash

@@ -221,6 +221,7 @@ _fzf_complete_telnet() {
 _fzf_complete_ssh() {
   _fzf_complete '+m' "$@" < <(
     cat <(cat ~/.ssh/config /etc/ssh/ssh_config 2> /dev/null | \grep -i '^host' | \grep -v '*') \
+        <(\grep -oE '^[^ ]+' ~/.ssh/known_hosts | tr ',' '\n' | awk '{ print $1 " " $1 }') \
         <(\grep -v '^\s*\(#\|$\)' /etc/hosts | \grep -Fv '0.0.0.0') |
         awk '{if (length($2) > 0) {print $2}}' | sort -u
   )

shell/completion.zsh

@@ -110,6 +110,7 @@ _fzf_complete_telnet() {
 _fzf_complete_ssh() {
   _fzf_complete '+m' "$@" < <(
     cat <(cat ~/.ssh/config /etc/ssh/ssh_config 2> /dev/null | \grep -i '^host' | \grep -v '*') \
+      <(\grep -oE '^[^ ]+' ~/.ssh/known_hosts | tr ',' '\n' | awk '{ print $1 " " $1 }') \
         <(\grep -v '^\s*\(#\|$\)' /etc/hosts | \grep -Fv '0.0.0.0') |
         awk '{if (length($2) > 0) {print $2}}' | sort -u
   )