staging: qlge: fix comparison to NULL warning

Fix comparison to NULL by replacing with !ptr instead.
 Issue detected by checkpatch.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Link: https://lore.kernel.org/r/20191010214006.23677-4-jbi.octave@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/qlge/qlge_dbg.c

@@ -1805,7 +1805,7 @@ void ql_dump_hw_cb(struct ql_adapter *qdev, int size, u32 bit, u16 q_id)
 	pr_err("%s: Enter\n", __func__);
 
 	ptr = kmalloc(size, GFP_ATOMIC);
-	if (ptr == NULL)
+	if (!ptr)
 		return;
 
 	if (ql_write_cfg(qdev, ptr, size, bit, q_id)) {