Always send xsel logfile to /dev/null

We don't want this logging to disk, but /dev/stderr doesn't always work
(see #81). Let's just stop all logging to avoid more shenanigans.

clipmenu

@@ -68,5 +68,5 @@ if ! [[ -f "$file" ]]; then
 fi
 
 for selection in clipboard primary; do
-    xsel --logfile /dev/stderr -i --"$selection" < "$file"
+    xsel --logfile /dev/null -i --"$selection" < "$file"
 done

clipmenud

@@ -21,19 +21,8 @@ has_clipnotify=0
 # shellcheck disable=SC2206
 cm_selections=( $CM_SELECTIONS )
 
-
-xsel_log=/dev/null
-for file in /proc/self/fd/2 /dev/stderr; do
-    [[ -f "$file" ]] || continue
-    # In Linux, it's not possible to write to a socket represented by a file
-    # (for example, /dev/stderr or /proc/self/fd/2). See issue #54.
-    [[ -f "$(readlink -m "$file")" ]] || continue
-    xsel_log="$file"
-    break
-done
-
 _xsel() {
-    timeout 1 xsel --logfile "$xsel_log" "$@"
+    timeout 1 xsel --logfile /dev/null "$@"
 }
 
 get_first_line() {

tests/test-clipmenu

@@ -81,8 +81,8 @@ grep -Fxq 'dmenu line 1 stdin: Selected text 2. (2 lines)' "$temp"
 grep -Fxq 'dmenu line 2 stdin: Selected text. (2 lines)' "$temp"
 
 # xsel should copy both to clipboard *and* primary
-grep -Fxq 'xsel args: --logfile /dev/stderr -i --clipboard' "$temp"
+grep -Fxq 'xsel args: --logfile /dev/null -i --clipboard' "$temp"
-grep -Fxq 'xsel args: --logfile /dev/stderr -i --primary' "$temp"
+grep -Fxq 'xsel args: --logfile /dev/null -i --primary' "$temp"
 
 grep -Fxq 'xsel line 1 stdin: Selected text.' "$temp"
 grep -Fxq "xsel line 2 stdin: Yes, it's selected text." "$temp"