[doc] add --with-zstd to INSTALL

INSTALL

@@ -18,11 +18,10 @@ unpack it by ::
 compile and install it with ::
 
   $ cd lighttpd-1.4.xx
+  $ ./autogen.sh
   $ ./configure -C
-  $ make
-  $ su -
-  # make install
-  # exit
+  $ make check
+  $ /usr/bin/sudo make install
 
 take look at the configfile in ./doc/lighttpd.conf,
 make your own copy of that file and modify it for your needs.
@@ -107,6 +106,8 @@ optional packages for optional features ::
   wolfssl-devel
   zlib                # zlib       ./configure --with-zlib
   zlib-devel
+  zstd                # zstd       ./configure --with-zstd
+  libzstd-devel
 
 more options: ./configure --help
 
@@ -181,12 +182,12 @@ build using CMake and Xcode on Mac OS X with MacPorts
   $ xcodebuild --license
   $ xcode-select --install
   $ sudo port selfupdate
-  $ sudo port install autoconf automake cmake libtool m4 pcre pkgconfig zlib brotli openssl libxml sqlite3 openldap libunwind libunwind-headers mysql57 libev gdbm openldap ossp-uuid
+  $ sudo port install autoconf automake cmake libtool m4 pcre pkgconfig zlib zstd brotli openssl libxml sqlite3 openldap libunwind libunwind-headers mysql57 libev gdbm openldap ossp-uuid
   # Note: some of the above require more fiddling to configure with CMake...
 
   # cmake and build
   # (all -DWITH_... flags below are optional)
-  $ cmake -Wno-dev -DWITH_OPENSSL=1 -DWITH_LUA=1 -DWITH_ZLIB=1 -DWITH_BROTLI=1 -DWITH_WEBDAV_PROPS=1 .
+  $ cmake -Wno-dev -DWITH_OPENSSL=1 -DWITH_LUA=1 -DWITH_ZLIB=1 -DWITH_ZSTD=1 -DWITH_BROTLI=1 -DWITH_WEBDAV_PROPS=1 .
   $ make -j 4
   $ make test