glsl: Also strdup the names of uniform list entries for >vec4 types.

Fixes double-free since the fix to free all of the uniform list.
diff --git a/src/glsl/linker.cpp b/src/glsl/linker.cpp
index b256574..2dc5697 100644
--- a/src/glsl/linker.cpp
+++ b/src/glsl/linker.cpp
@@ -843,7 +843,7 @@
 
 	    n->u[0].Name = strdup(var->name);
 	    for (unsigned j = 1; j < vec4_slots; j++)
-	       n->u[j].Name = n->u[0].Name;
+	       n->u[j].Name = strdup(var->name);
 
 	    hash_table_insert(ht, n, n->u[0].Name);
 	    uniforms.push_tail(& n->link);