drm/ast: Request PCI BAR with devres

ast currently ioremaps two PCI BARs using pcim_iomap(). It does not perform
a request on the regions, however, which would make the driver a bit more
robust.

PCI now offers pcim_iomap_region(), a managed function which both requests
and ioremaps a BAR.

Replace pcim_iomap() with pcim_iomap_region().

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20240807083018.8734-4-pstanner@redhat.com
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Dave Airlie <airlied@redhat.com>

Author: Philipp Stanner

drivers/gpu/drm/ast/ast_drv.c

@@ -287,9 +287,9 @@ static int ast_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (ret)
 		return ret;
 
-	regs = pcim_iomap(pdev, 1, 0);
-	if (!regs)
-		return -EIO;
+	regs = pcim_iomap_region(pdev, 1, "ast");
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
 
 	if (pdev->revision >= 0x40) {
 		/*
@@ -311,9 +311,9 @@ static int ast_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 		if (len < AST_IO_MM_LENGTH)
 			return -EIO;
-		ioregs = pcim_iomap(pdev, 2, 0);
-		if (!ioregs)
-			return -EIO;
+		ioregs = pcim_iomap_region(pdev, 2, "ast");
+		if (IS_ERR(ioregs))
+			return PTR_ERR(ioregs);
 	} else {
 		/*
 		 * Anything else is best effort.