drm/xe: Update GuC/HuC firmware autoselect logic

Update the logic to autoselect GuC/HuC for the platforms with the
following improvements:

- Document what is the firmware file that is expected to be
  loaded and what is checked from blob headers

- When the platform is under force-probe it's desired to enforce
  the full-version requirement so the correct firmware is used
  before widespread adoption and backward-compatibility
  commitments

- Directory from which we expect firmware blobs to be available in
  upstream linux-firmware repository depends on the platform: for
  the ones supported by i915 it uses the i915/ directory, but the ones
  expected to be supported by xe, it's on the xe/ directory. This
  means that for platforms in the intersection, the firmware is
  loaded from a different directory, but that is not much important
  in the firmware repo and it avoids firmware duplication.

- Make the table with the firmware definitions clearly state the
  versions being expected. Now with macros to select the version it's
  possible to choose between full-version/major-version for GuC and
  full-version/no-version for HuC. These are similar to the macros used
  in i915, but implemented in a slightly different way to avoid
  duplicating the macros for each firmware/type and functionality,
  besides adding the support for different directories.

- There is no check added regarding force-probe since xe should
  reuse the same firmware files published for i915 for past
  platforms. This can be improved later with additional
  kunit checking against a hardcoded list of platforms that
  falls in this category.

- As mentioned in the TODO, the major version fallback was not
  implemented before as currently each platform only supports one
  major. That can be easily added later.

- GuC version for MTL and PVC were updated to 70.6.4, using the exact
  full version, while the

After this the GuC firmware used by PVC changes to pvc_guc_70.5.2.bin
since it's using a file not published yet.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Link: https://lore.kernel.org/r/20230324051754.1346390-4-lucas.demarchi@intel.comSigned-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/xe/xe_uc_fw.h

@@ -175,6 +175,6 @@ static inline u32 xe_uc_fw_get_upload_size(struct xe_uc_fw *uc_fw)
 	return __xe_uc_fw_get_upload_size(uc_fw);
 }
 
-#define XE_UC_FIRMWARE_URL "https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/tree/i915"
+#define XE_UC_FIRMWARE_URL "https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git"
 
 #endif

drivers/gpu/drm/xe/xe_uc_fw_types.h

@@ -78,6 +78,13 @@ struct xe_uc_fw {
 	const char *path;
 	/** @user_overridden: user provided path to uC firmware via modparam */
 	bool user_overridden;
+	/**
+	 * @full_ver_required: driver still under development and not ready
+	 * for backward-compatible firmware. To be used only for **new**
+	 * platforms, i.e. still under require_force_probe protection and not
+	 * supported by i915.
+	 */
+	bool full_ver_required;
 	/** @size: size of uC firmware including css header */
 	size_t size;