Improve tests/scripts/depends.py code

As suggested by gilles-peskine-arm.

Co-authored-by: Gilles Peskine <gilles.peskine@arm.com>
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/tests/scripts/depends.py b/tests/scripts/depends.py
index 2f0fbc2..3e8a2b0 100755
--- a/tests/scripts/depends.py
+++ b/tests/scripts/depends.py
@@ -151,13 +151,12 @@
     if value is False:
         log_command(['config.py', 'unset', option])
         conf.unset(option)
+    elif value is True:
+        log_command(['config.py', 'set', option])
+        conf.set(option)
     else:
-        if value is True:
-            log_command(['config.py', 'set', option])
-            conf.set(option)
-        else:
-            log_command(['config.py', 'set', option, value])
-            conf.set(option, value)
+        log_command(['config.py', 'set', option, value])
+        conf.set(option, value)
     return True
 
 def set_reference_config(conf, options, colors):