Add --interval flag to podman wait

Waiting uses a lot of CPU, so drop back to checking once/second
and allow user to pass in the interval.

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

completions/bash/podman

@@ -2012,7 +2012,9 @@ _podman_wait() {
      local boolean_options="
         --help
         -h
-        -l
+        -i
+	-l
+        --interval
         --latest"
     case "$cur" in
         -*)