drm/i915: Pass size to oprom_get_vbt

oprom_get_vbt will later be used to show the contents of vbt for which
the size of vbt is needed.

v2: Avoid overuse of *size and remove dummy size variable in
    intel_bios_init(Jani)

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240228213235.2495611-2-radhakrishna.sripada@intel.com

drivers/gpu/drm/i915/display/intel_bios.c

@@ -3058,7 +3058,8 @@ static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915)
 	return NULL;
 }
 
-static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915)
+static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915,
+					size_t *sizep)
 {
 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
 	void __iomem *p = NULL, *oprom;
@@ -3107,6 +3108,9 @@ static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915)
 
 	pci_unmap_rom(pdev, oprom);
 
+	if (sizep)
+		*sizep = vbt_size;
+
 	drm_dbg_kms(&i915->drm, "Found valid VBT in PCI ROM\n");
 
 	return vbt;
@@ -3156,7 +3160,7 @@ void intel_bios_init(struct drm_i915_private *i915)
 	}
 
 	if (!vbt) {
-		oprom_vbt = oprom_get_vbt(i915);
+		oprom_vbt = oprom_get_vbt(i915, NULL);
 		vbt = oprom_vbt;
 	}