Fix a few incorrectly checked [io_]remap_pfn_range() calls

Nico Golde reports a few straggling uses of [io_]remap_pfn_range() that
really should use the vm_iomap_memory() helper.  This trivially converts
two of them to the helper, and comments about why the third one really
needs to continue to use remap_pfn_range(), and adds the missing size
check.

Reported-by: Nico Golde <nico@ngolde.de>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org.
static ssize_t name_show(struct device *dev,
			 struct device_attribute *attr, char *buf)
{
	struct uio_device *idev = dev_get_drvdata(dev);
	return sprintf(buf, "%s\n", idev->info->name);
}

static ssize_t name_show(struct device *dev,
			 struct device_attribute *attr, char *buf)
{
	struct uio_device *idev = dev_get_drvdata(dev);
	return sprintf(buf, "%s\n", idev->info->name);
}
