drm/i915/uncore: cast iomem to avoid sparse warning

drmm_add_action_or_reset() is unaware of __iomem and the pointer needs
to be a plain void *. Cast __iomem away and back while the pointer goes
through drmm.

drivers/gpu/drm/i915/intel_uncore.c:2463:17: warning: incorrect type in argument 1 (different address spaces)
drivers/gpu/drm/i915/intel_uncore.c:2463:17:    expected void volatile [noderef] __iomem *addr
drivers/gpu/drm/i915/intel_uncore.c:2463:17:    got void *regs
drivers/gpu/drm/i915/intel_uncore.c:2494:16: warning: incorrect type in argument 3 (different address spaces)
drivers/gpu/drm/i915/intel_uncore.c:2494:16:    expected void *data
drivers/gpu/drm/i915/intel_uncore.c:2494:16:    got void [noderef] __iomem *regs

Cc: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230207124026.2105442-2-jani.nikula@intel.com

drivers/gpu/drm/i915/intel_uncore.c

@@ -2460,7 +2460,7 @@ static int i915_pmic_bus_access_notifier(struct notifier_block *nb,
 
 static void uncore_unmap_mmio(struct drm_device *drm, void *regs)
 {
-	iounmap(regs);
+	iounmap((void __iomem *)regs);
 }
 
 int intel_uncore_setup_mmio(struct intel_uncore *uncore, phys_addr_t phys_addr)
@@ -2491,7 +2491,8 @@ int intel_uncore_setup_mmio(struct intel_uncore *uncore, phys_addr_t phys_addr)
 		return -EIO;
 	}
 
-	return drmm_add_action_or_reset(&i915->drm, uncore_unmap_mmio, uncore->regs);
+	return drmm_add_action_or_reset(&i915->drm, uncore_unmap_mmio,
+					(void __force *)uncore->regs);
 }
 
 void intel_uncore_init_early(struct intel_uncore *uncore,