misc: sram: fix check of devm_ioremap*() return value

Both devm_ioremap() and devm_ioremap_wc() functions return either
a pointer to valid iomem region or NULL, check for IS_ERR() is improper
and may result in oops on error path. Now on error -ENOMEM is returned.

Fixes: 0ab163ad1ea0 ("misc: sram: switch to ioremap_wc from ioremap")
Signed-off-by: Vladimir Zapolskiy <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/misc/sram.c

···
 		sram->virt_base = devm_ioremap(sram->dev, res->start, size);
 	else
 		sram->virt_base = devm_ioremap_wc(sram->dev, res->start, size);
-	if (IS_ERR(sram->virt_base))
-		return PTR_ERR(sram->virt_base);
+	if (!sram->virt_base)
+		return -ENOMEM;
 
 	sram->pool = devm_gen_pool_create(sram->dev, ilog2(SRAM_GRANULARITY),
 					  NUMA_NO_NODE, NULL);