drm/amdgpu: Report ras_num_recs in debugfs

Report the number of records stored in the RAS EEPROM table in debugfs.

This can be used by user-space to calculate the capacity of the RAS EEPROM
table since "bad_page_cnt_threshold" is also reported in the same place in
debugfs.

See commit 7fb64071 ("drm/amdgpu: Add bad_page_cnt_threshold to debugfs").

ras_num_recs can already be inferred by dumping the RAS EEPROM table, also in
the same debugfs location, see commit reference c65b0805 (drm/amdgpu:
RAS EEPROM table is now in debugfs, 2021-04-08). This commit makes it an
integer value easily shown in a single file.

Cc: Alex Deucher <Alexander.Deucher@amd.com>
Cc: Hawking Zhang <Hawking.Zhang@amd.com>
Cc: Tao Zhou <tao.zhou1@amd.com>
Cc: Stanley Yang <Stanley.Yang@amd.com>
Cc: John Clements <john.clements@amd.com>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
Link: https://lore.kernel.org/r/20230603051043.211548-1-luben.tuikov@amd.comAcked-by: Alex Deucher <Alexander.Deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c

@@ -1491,6 +1491,7 @@ static int amdgpu_ras_sysfs_remove_all(struct amdgpu_device *adev)
 static struct dentry *amdgpu_ras_debugfs_create_ctrl_node(struct amdgpu_device *adev)
 {
 	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
+	struct amdgpu_ras_eeprom_control *eeprom = &con->eeprom_control;
 	struct drm_minor  *minor = adev_to_drm(adev)->primary;
 	struct dentry     *dir;
 
@@ -1501,6 +1502,7 @@ static struct dentry *amdgpu_ras_debugfs_create_ctrl_node(struct amdgpu_device *
 			    &amdgpu_ras_debugfs_eeprom_ops);
 	debugfs_create_u32("bad_page_cnt_threshold", 0444, dir,
 			   &con->bad_page_cnt_threshold);
+	debugfs_create_u32("ras_num_recs", 0444, dir, &eeprom->ras_num_recs);
 	debugfs_create_x32("ras_hw_enabled", 0444, dir, &adev->ras_hw_enabled);
 	debugfs_create_x32("ras_enabled", 0444, dir, &adev->ras_enabled);
 	debugfs_create_file("ras_eeprom_size", S_IRUGO, dir, adev,