mtd: gpmi: Remove noisy error message

mx28evk board has a socket for NAND flash that comes with no NAND flash
populated, and then we get this message on every boot:

[    1.657603] gpmi-nand 8000c000.gpmi-nand: driver registration failed: -19

which is not very helpful, so get rid of this error message.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

drivers/mtd/nand/gpmi-nand/gpmi-nand.c

@@ -2029,7 +2029,6 @@ static int gpmi_nand_probe(struct platform_device *pdev)
 exit_nfc_init:
 	release_resources(this);
 exit_acquire_resources:
-	dev_err(this->dev, "driver registration failed: %d\n", ret);
 
 	return ret;
 }