Abort completion file loading earlier if required commands are not available.

It's follow up of 9af6f3504e8c94e5ead187b7cd223bd481548957

completions/pkgtools

@@ -1,7 +1,7 @@
 # bash completion for Slackware Linux pkgtools
 
-[ -f /etc/slackware-version ] &&
-{
+[ -f /etc/slackware-version ] || return
+
 
 have pkgtool &&
 _pkgtool()
@@ -123,5 +123,3 @@ _makepkg()
 
 have explodepkg &&
 complete -o plusdirs -f -X '!*.t[bglx]z' explodepkg
-
-}

completions/rpm2tgz

@@ -1,6 +1,7 @@
 # Slackware rpm2tgz completion.
 
-have rpm2tgz &&
+have rpm2tgz || return
+
 _rpm2tgz()
 {
     COMPREPLY=()

completions/sbopkg

@@ -1,6 +1,7 @@
 # bash completion for sbopkg tool
 
-have sbopkg &&
+have sbopkg || return
+
 _sbopkg()
 {
     COMPREPLY=()

completions/slackpkg

@@ -1,6 +1,7 @@
 # bash completion for slackpkg tool
 
-have slackpkg &&
+have slackpkg || return
+
 _slackpkg()
 {
     COMPREPLY=()