mips: cm: add missing iounmap() on error in mips_cm_probe()

Add the missing iounmap() of iounmap(mips_gcr_base) before
return from mips_cm_probe() in the error handling case.
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/kernel/mips-cm.c

@@ -266,6 +266,7 @@ int mips_cm_probe(void)
 	if ((base_reg & CM_GCR_BASE_GCRBASE) != addr) {
 		pr_err("GCRs appear to have been moved (expected them at 0x%08lx)!\n",
 		       (unsigned long)addr);
+		iounmap(mips_gcr_base);
 		mips_gcr_base = NULL;
 		return -ENODEV;
 	}