drm/xe: Open-code GGTT MMIO access protection

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/gpu/drm/xe/xe_ggtt.c",
                        "drivers/gpu/drm/xe/xe_ggtt_types.h"
                    ],
                    "versions": [
                        {
                            "version": "919bb54e989c1edef87e9797be125c94c450fc65",
                            "lessThan": "e2b424aadecb640f9e037b2891191cf8fd4c64cf",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "919bb54e989c1edef87e9797be125c94c450fc65",
                            "lessThan": "1e9e2640d870d4837bcfdc220cb2c99ae5ee119f",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "919bb54e989c1edef87e9797be125c94c450fc65",
                            "lessThan": "76326dc06d8793c2c81c31cc0115dbc348de2f88",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "919bb54e989c1edef87e9797be125c94c450fc65",
                            "lessThan": "01f2557aa684e514005541e71a3d01f4cd45c170",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                }

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/gpu/drm/xe/xe_ggtt.c",
                        "drivers/gpu/drm/xe/xe_ggtt_types.h"
                    ],
                    "versions": [
                        {
                            "version": "6.12",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.12",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.78",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.20",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19.10",
                            "lessThanOrEqual": "6.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }