treewide: yet more log_*_errno + return simplifications

Using:
find . -name '*.[ch]' | while read f; do perl -i.mmm -e \
 'local $/;
  local $_=<>;
  s/(if\s*\([^\n]+\))\s*{\n(\s*)(log_[a-z_]*_errno\(\s*([->a-zA-Z_]+)\s*,[^;]+);\s*return\s+\g4;\s+}/\1\n\2return \3;/msg;
  print;'
 $f
done

And a couple of manual whitespace fixups.

src/update-utmp/update-utmp.c

@@ -189,10 +189,8 @@ static int on_runlevel(Context *c) {
         q = utmp_get_runlevel(&previous, NULL);
 
         if (q < 0) {
-                if (q != -ESRCH && q != -ENOENT) {
-                        log_error_errno(q, "Failed to get current runlevel: %m");
-                        return q;
-                }
+                if (q != -ESRCH && q != -ENOENT)
+                        return log_error_errno(q, "Failed to get current runlevel: %m");
 
                 previous = 0;
         }