initial_pins: Add check to reduce compile time size when not in use

Add a check to the start of initial_pins_setup() to make it easier for
gcc to optimize the code if it is not in use.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

src/initial_pins.c

@@ -16,6 +16,8 @@ DECL_CTR("DECL_INITIAL_PINS " __stringify(CONFIG_INITIAL_PINS));
 void
 initial_pins_setup(void)
 {
+    if (sizeof(CONFIG_INITIAL_PINS) <= 1)
+        return;
     int i;
     for (i=0; i<initial_pins_size; i++) {
         const struct initial_pin_s *ip = &initial_pins[i];