pan/midgard: Don't try to free NULL in LCRA

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Fixes: 12e393bacf ("panfrost: add lcra_free() to free lcra state")

src/panfrost/midgard/lcra.c

@@ -69,6 +69,9 @@ lcra_alloc_equations(
 void
 lcra_free(struct lcra_state *l)
 {
+        if (!l)
+                return;
+
         free(l->alignment);
         free(l->linear);
         free(l->modulus);