drm/xe: Return if kobj creation is failed

Return after warning regarding kobj creation failure.

Fixes: 4ae3aeab32d7 ("drm/xe: Add vram frequency sysfs attributes")
Cc: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Cc: Tejas Upadhyay <tejas.upadhyay@intel.com>
Cc: Bommu Krishnaiah <krishnaiah.bommu@intel.com>
Reviewed-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240313150545.2830408-2-himal.prasad.ghimiray@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
(cherry picked from commit 989d07ac6bb7d269e975f85e8f683f496faa0380)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

drm/xe: Fix typo in vram frequency sysfs documentation

Fix function naming and description for xe_vram_freq_sysfs_init
function.

v2: Add fixes tag (Riana)
Fix review comments (Lucas)

Fixes: 4ae3aeab32d7 ("drm/xe: Add vram frequency sysfs attributes")
Signed-off-by: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Reviewed-by: Riana Tauro <riana.tauro@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240117043215.2598677-1-sujaritha.sundaresan@intel.com

drm/xe: Add vram frequency sysfs attributes

Add vram frequency sysfs attributes under the below hierarchy;

/device/tile#/memory/freq0
|-max_freq
|-min_freq

v2: Drop "vram" from attribute names (Rodrigo)

v3: Add documentation for new sysfs (Riana)
Drop prefix from XEHP_PCODE_FREQUENCY_CONFIG (Riana)

v4: Create sysfs under tile#/freq0 after removal of
physical_memsize attrbute

v5: Revert back to creating sysfs under tile#/memory/freq0
Remove definition of GT_FREQUENCY_MULTIPLIER (Rodrigo)

v6: Rename attributes to max/min_freq (Anshuman)
Fix review comments (Rodrigo)

v7: Make documentation more verbose
Move sysfs to separate file (Anshuman)

v8: Fix platform specific conditions and add kernel doc (Anshuman)
Fix typos and remove redundant headers (Riana)

v9: Fix typo (Riana)
Change function name to include "sysfs" (Lucas)

Signed-off-by: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Reviewed-by: Anshuman Gupta <anshuman.gupta@intel.com>
Link: https://lore.kernel.org/r/20240109110418.2065101-1-sujaritha.sundaresan@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>