Remove unneeded file labels.

A previous commit (a83e0cc) already labels these with genfs_context,
which has better performance.

Bug: 62413700
Test: Built, flashed, and booted.  Verified that the files have
the correct context.

Change-Id: I464b0df30fabfc5f1c7cd7430e53e8d04bfacb53

private/file_contexts

@@ -452,28 +452,6 @@
 # LocalTransport (backup) uses this subtree
 /data/cache/backup(/.*)?	u:object_r:cache_private_backup_file:s0
 
-###########################################
-# debug-only tracing
-#
-/sys/kernel/debug/tracing/events/sync/enable                         u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/workqueue/enable                    u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/regulator/enable                    u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/pagecache/enable                    u:object_r:tracing_shell_writable_debug:s0
-
-/sys/kernel/debug/tracing/events/irq/enable                          u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/ipi/enable                          u:object_r:tracing_shell_writable_debug:s0
-
-/sys/kernel/debug/tracing/events/f2fs/f2fs_sync_file_enter/enable    u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/f2fs/f2fs_sync_file_exit/enable     u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/f2fs/f2fs_write_begin/enable        u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/f2fs/f2fs_write_end/enable          u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/ext4/ext4_da_write_begin/enable     u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/ext4/ext4_da_write_end/enable       u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/ext4/ext4_sync_file_enter/enable    u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/ext4/ext4_sync_file_exit/enable     u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/block/block_rq_issue/enable         u:object_r:tracing_shell_writable_debug:s0
-/sys/kernel/debug/tracing/events/block/block_rq_complete/enable      u:object_r:tracing_shell_writable_debug:s0
-
 #############################
 # asec containers
 /mnt/asec(/.*)?             u:object_r:asec_apk_file:s0