title: How to specify which kernel to build with bitbake/yocto
body: <p>I am working on generating a new BSP using yocto daisy.  When I build my image I get these warnings:</p>
  
  <pre><code>NOTE: Resolving any missing task queue dependencies
  NOTE: multiple providers are available for virtual/kernel (my-kernel, linux-dummy)
  NOTE: consider defining a PREFERRED_PROVIDER entry to match virtual/kernel
  NOTE: multiple providers are available for runtime kernel-modules (my-kernel, linux-dummy)
  NOTE: consider defining a PREFERRED_PROVIDER entry to match kernel-modules
  </code></pre>
  
  <p>I can't understand how to define my preferred provider for the kernel.  From what I have read I should just need to add it to the meta-myLayer/conf/machine/myMachine.conf
  Which I did, as such:</p>
  
  <pre><code>KERNEL_IMAGETYPE = "zImage"
  KERNEL_DEVICETREE = "${S}/arch/arm/boot/dts/myTree.dtb"
  KERNEL_EXTRA_ARGS += "LOADADDR=${UBOOT_ENTRYPOINT}"
  #  use this kernel and version
  PREFERRED_PROVIDER_virtual/kernel = "linux-yocto"
  PREFERRED_VERSION_linux-yocto = "3.14%"
  </code></pre>
  
  <p>Yocto/bitbake seem to be ignoring these lines.<br>
  Also, to be clear I also have the machine name set correctly in build/conf/local.conf</p>
  
  <p>Is there something else I need to change to get this to work? Or is Yocto just that broken?</p>