update readme

README.md

@@ -7,11 +7,11 @@ Code must be located in `poky/` directory. Navigate to `poky/` and run:
 git clone https://github.com/Elphel/linux-elphel.git
 ```
 ##Generating links and headers
-Links between project tree and kernel source tree are generated by Bitbake during 'unpack' task when using `meta-elphel393`. Some required header files are automatically generated during the build process.
+Links between project tree and kernel source tree are generated by Bitbake during 'link' task when using `meta-elphel393`. Some required header files are automatically generated during the build process.
 ```
 . ./oe-init-build-env
 bitbake linux-xlnx -c clean -f
-bitbake linux-xlnx -c unpack -f
+bitbake linux-xlnx -c link -f
 bitbake linux-xlnx -f
 ```
 ##Importing project into Eclipse