Revert "Add the sysrq_file special file and give ADB write access."

This rule doesn't work, as /proc/sysrq-trigger isn't properly labeled.
Revert this change for now.

This reverts commit bb2591e56f0b88570e8bed0008b932bf7c51f533.
diff --git a/adbd.te b/adbd.te
index a92338f..4026fcb 100644
--- a/adbd.te
+++ b/adbd.te
@@ -35,6 +35,3 @@
 # XXX Run screencap in a separate domain?
 binder_use(adbd)
 binder_call(adbd, surfaceflinger)
-
-# Write to the sysrq file
-allow adbd sysrq_file:file w_file_perms;
diff --git a/file.te b/file.te
index 06ceecc..29b2106 100644
--- a/file.te
+++ b/file.te
@@ -81,8 +81,6 @@
 type bluetooth_efs_file, file_type;
 # Downloaded files
 type download_file, file_type;
-# The sysrq special file
-type sysrq_file, file_type;
 
 # Socket types
 type adbd_socket, file_type;
diff --git a/file_contexts b/file_contexts
index 8906e38..3d885b1 100644
--- a/file_contexts
+++ b/file_contexts
@@ -211,6 +211,3 @@
 # asec containers
 /mnt/asec(/.*)?         u:object_r:asec_apk_file:s0
 /data/app-asec(/.*)?    u:object_r:asec_image_file:s0
-#############################
-# special /proc files
-/proc/sysrq-trigger  u:object_r:sysrq_file:s0