fixed shellcheck SC2015 violation

SC2015 (info): Note that A && B || C is not if-then-else. C may run when A is true

.tmux.conf

@@ -358,7 +358,9 @@ run 'cut -c3- "$TMUX_CONF" | sh -s _apply_configuration'
 #       done
 #       ;;
 #   esac
-#   [ "$count" -ne 0 ] && charge=$(awk -v charge="$charge" -v count="$count" 'BEGIN { print charge / count }') || true
+#   if [ "$count" -ne 0 ]; then
+#     charge=$(awk -v charge="$charge" -v count="$count" 'BEGIN { print charge / count }')
+#   fi
 # }
 #
 # _battery_status() {
@@ -869,8 +871,10 @@ run 'cut -c3- "$TMUX_CONF" | sh -s _apply_configuration'
 #
 #   # ignore bindings with errors
 #   if ! tmux source-file "$cfg.in"; then
-#     verbose_flag=$(tmux source-file -v /dev/null 2> /dev/null && printf -- '-v' || true)
-#     while ! out=$(tmux source-file "$verbose_flag" "$cfg.in"); do
+#     if tmux source-file -v /dev/null 2> /dev/null; then
+#       verbose_flag='-v'
+#     fi
+#     while ! out=$(tmux source-file "${verbose_flag:+$verbose_flag}" "$cfg.in"); do
 #       line=$(printf "%s" "$out" | tail -1 | cut -d':' -f2)
 #       perl -n -i -e "if ($. != $line) { print }" "$cfg.in"
 #     done
@@ -1504,8 +1508,10 @@ run 'cut -c3- "$TMUX_CONF" | sh -s _apply_configuration'
 #
 #   if perl -n -e 'print if /^\s*(?:set|bind|unbind).+?#!important\s*$/' "$TMUX_CONF_LOCAL" 2>/dev/null > "$cfg.local"; then
 #     if ! tmux source-file "$cfg.local"; then
-#       verbose_flag=$(tmux source-file -v /dev/null 2> /dev/null && printf -- '-v' || true)
-#       while ! out=$(tmux source-file "$verbose_flag" "$cfg.local"); do
+#       if tmux source-file -v /dev/null 2> /dev/null; then
+#         verbose_flag='-v'
+#       fi
+#       while ! out=$(tmux source-file "${verbose_flag:+$verbose_flag}" "$cfg.local"); do
 #         line=$(printf "%s" "$out" | tail -1 | cut -d':' -f2)
 #         perl -n -i -e "if ($. != $line) { print }" "$cfg.local"
 #       done