accel/amdxdna: Expose per-client BO memory usage via fdinfo

accel/amdxdna: Expose per-client BO memory usage via fdinfo

Implement amdxdna_show_fdinfo() to report per-client memory usage,
including below driver-specific memory stat:
  - heap allocation
  - internal BO allocation
  - external BO allocation

Hook the implementation into the DRM fdinfo infrastructure via
drm_driver.show_fdinfo, while continuing to expose standard DRM
memory stat through drm_show_memory_stats().

This improves observability of per-process memory usage and aligns
with existing fdinfo reporting mechanisms used by other drivers.

Suggested-by: Ian Rogers <irogers@google.com>
Signed-off-by: Max Zhen <max.zhen@amd.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patch.msgid.link/20260409152259.176883-1-lizhi.hou@amd.com