improve compile docs

docs/compile/build_howto_openwrt.txt

@@ -1,7 +1,14 @@
 How to compile native programs for use in openwrt
 -------------------------------------------------
 
-1) Download latest SDK for your platform from https://downloads.openwrt.org
+1) Install required packages to the host system :
+
+debian,ubuntu : apt install build-essential patch libncurses-dev python3-distutils unzip gawk wget git
+fedora: dnf install make patch gcc g++ ncurses-devel git perl
+
+Other packages may be required on your distribution. Look for the errors.
+
+2) Download latest SDK for your target platform from https://downloads.openwrt.org
 
 examples :
 
@@ -11,12 +18,12 @@ cd openwrt-sdk-23.05.5-x86-64_gcc-12.3.0_musl.Linux-x86_64
 curl -o - https://downloads.openwrt.org/snapshots/targets/x86/64/openwrt-sdk-x86-64_gcc-13.3.0_musl.Linux-x86_64.tar.zst | tar --zstd -xvf -
 cd openwrt-sdk-x86-64_gcc-13.3.0_musl.Linux-x86_64
 
-2) Install required libs
+3) Install required libs
 
 ./scripts/feeds update base packages
 ./scripts/feeds install libnetfilter-queue zlib libcap
 
-3) Prepare openwrt package definitions
+4) Prepare openwrt package definitions
 
 cp -R /opt/zapret/docs/compile/openwrt/. .
 cp -R /opt/zapret/tpws package/zapret/tpws
@@ -25,12 +32,26 @@ cp -R /opt/zapret/mdig package/zapret/mdig
 cp -R /opt/zapret/ip2net package/zapret/ip2net
 rm -f package/zapret/tpws/tpws/tpws package/zapret/nfqws/nfq/nfqws package/zapret/mdig/mdig/mdig package/zapret/ip2net/ip2net/ip2net
 
-4) Compile
+5) Prepare .config
+
+make defconfig
+
+If you only need bins without packages comment 'CONFIG_AUTOREMOVE=y' line in .config
+
+6) Compile
+
+dynamic build : make package/{tpws,nfqws,mdig,ip2net}/compile
+static build :  make CFLAGS=-static package/{tpws,nfqws,mdig,ip2net}/compile
+
+7) Get result
 
-make package/{tpws,nfqws,mdig,ip2net}/compile
+executables only : build_dir/target/<progname>
+ipk or apk packages : bin/packages/*/base
 
-5) Get result
+8) Installating to openwrt to use with zapret
 
-ls -l bin/packages/*/base
-# take your ipk or apk from there
-# zlib-dev is not required
+zapret with or without binaries should be already installed in /opt/zapret.
+Install ipk's or apk's with all compiled progs using opkg or apk.
+Bins are placed to /opt/zapret/binaries/my.
+Or copy binaries there manually and set chmod 755 to them.
+Run install_bin.sh or install_easy.sh. They will use bins in 'my' folder.