Add type for /system/bin/tcpdump.

We add this type with the intent to expose /system/bin/tcpdump to
vendor on userdebug devices only.

Bug: 111243627
Test: device boots /system/bin/tcpdump correctly labeled as
tcpdump_exec, can browse internet, turn wifi on/off
Change-Id: Icb35e84c87120d198fbb2b44edfa5edf6021d0f0

private/compat/28.0/28.0.cil

@@ -1571,6 +1571,7 @@
     system_linker_exec
     system_seccomp_policy_file
     system_security_cacerts_file
+    tcpdump_exec
     system_zoneinfo_file
 ))
 (typeattributeset systemkeys_data_file_28_0 (systemkeys_data_file))

private/file_contexts

@@ -198,6 +198,7 @@
 /system/bin/sload_f2fs	--	u:object_r:e2fs_exec:s0
 /system/bin/make_f2fs	--	u:object_r:e2fs_exec:s0
 /system/bin/fsck_msdos	--	u:object_r:fsck_exec:s0
+/system/bin/tcpdump	--	u:object_r:tcpdump_exec:s0
 /system/bin/tune2fs	--	u:object_r:fsck_exec:s0
 /system/bin/toolbox	--	u:object_r:toolbox_exec:s0
 /system/bin/toybox	--	u:object_r:toolbox_exec:s0

public/file.te

@@ -146,6 +146,8 @@ type system_seccomp_policy_file, system_file_type, file_type;
 type apex_key_file, system_file_type, file_type;
 # Default type for cacerts in /system/etc/security/cacerts/*.
 type system_security_cacerts_file, system_file_type, file_type;
+# Default type for /system/bin/tcpdump.
+type tcpdump_exec, system_file_type, exec_type, file_type;
 # Default type for zoneinfo files in /system/usr/share/zoneinfo/*.
 type system_zoneinfo_file, system_file_type, file_type;