delete tengine syslog support

auto/options

@@ -162,7 +162,6 @@ NGX_DSO_ABI_ALL_TAG="
     with-http
     with-http-cache
     with-ipv6
-    with-syslog
     with-http-gzip
     with-http-gzip-static
     with-http-ssi
@@ -182,7 +181,6 @@ NGX_DSO_DEBUG_TAG=0x00000001
 NGX_DSO_HTTP_TAG=0x00000002
 NGX_DSO_CACHE_TAG=0x00000004
 NGX_DSO_IPV6_TAG=0x00000008
-NGX_DSO_SYSLOG_TAG=0x00000010
 NGX_DSO_GZIP_TAG=0x00000020
 NGX_DSO_GZIP_STATIC_TAG=0x00000040
 NGX_DSO_SSI_TAG=0x00000080
@@ -377,8 +375,6 @@ NGX_CPU_CACHE_LINE=
 
 NGX_FORCE_EXIT=NO
 
-NGX_SYSLOG=YES
-
 NGX_POST_CONF_MSG=
 
 
@@ -437,9 +433,6 @@ do
 
         --with-force-exit)                         NGX_FORCE_EXIT=YES         ;;
 
-        --with-syslog)                             NGX_SYSLOG=YES              ;;
-        --without-syslog)                          NGX_SYSLOG=NO              ;;
-
         --without-dso)                             NGX_DSO=NO                 ;;
 
         --without-http)                            HTTP=NO                    ;;
@@ -778,8 +771,6 @@ cat << END
   --with-ipv6                        enable IPv6 support
   --with-force-exit                  enable force_exit support
 
-  --without-syslog                   disable syslog logging
-
   --without-dso                      disable dso module load
 
   --with-http_v2_module              enable ngx_http_v2_module

auto/sources

@@ -154,9 +154,6 @@ AIO_SRCS="src/event/modules/ngx_aio_module.c \
 FILE_AIO_SRCS="src/os/unix/ngx_file_aio_read.c"
 LINUX_AIO_SRCS="src/os/unix/ngx_linux_aio_read.c"
 
-#SYSLOG_DEPS="src/os/unix/ngx_syslog.h"
-#SYSLOG_SRCS="src/os/unix/ngx_syslog.c"
-
 PIPE_DEPS="src/os/unix/ngx_pipe.h"
 PIPE_SRCS="src/os/unix/ngx_pipe.c"
 

auto/unix

@@ -572,12 +572,6 @@ if [ $NGX_IPV6 = YES ]; then
 fi
 
 
-if [ $NGX_SYSLOG = YES ]; then
-    CORE_DEPS="$CORE_DEPS $SYSLOG_DEPS"
-    CORE_SRCS="$CORE_SRCS $SYSLOG_SRCS"
-fi
-
-
 if [ $NGX_BACKTRACE = YES ]; then
     ngx_feature="BACKTRACE"
     ngx_feature_name=