drm/i915/perf: reconcile Excess struct member kernel-doc warnings

Document nested struct members with full names as described in
Documentation/doc-guide/kernel-doc.rst.

i915_perf_types.h:341: warning: Excess struct member 'ptr_lock' description in 'i915_perf_stream'
i915_perf_types.h:341: warning: Excess struct member 'head' description in 'i915_perf_stream'
i915_perf_types.h:341: warning: Excess struct member 'tail' description in 'i915_perf_stream'
3 warnings as Errors
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231226195432.10891-4-rdunlap@infradead.org

drivers/gpu/drm/i915/i915_perf_types.h

@@ -291,7 +291,8 @@ struct i915_perf_stream {
 		int size_exponent;
 
 		/**
-		 * @ptr_lock: Locks reads and writes to all head/tail state
+		 * @oa_buffer.ptr_lock: Locks reads and writes to all
+		 * head/tail state
 		 *
 		 * Consider: the head and tail pointer state needs to be read
 		 * consistently from a hrtimer callback (atomic context) and
@@ -313,7 +314,8 @@ struct i915_perf_stream {
 		spinlock_t ptr_lock;
 
 		/**
-		 * @head: Although we can always read back the head pointer register,
+		 * @oa_buffer.head: Although we can always read back
+		 * the head pointer register,
 		 * we prefer to avoid trusting the HW state, just to avoid any
 		 * risk that some hardware condition could * somehow bump the
 		 * head pointer unpredictably and cause us to forward the wrong
@@ -322,7 +324,8 @@ struct i915_perf_stream {
 		u32 head;
 
 		/**
-		 * @tail: The last verified tail that can be read by userspace.
+		 * @oa_buffer.tail: The last verified tail that can be
+		 * read by userspace.
 		 */
 		u32 tail;
 	} oa_buffer;