petalinux-features.conf: Allow bootin preferred provider to be overrideable
petalinux-features.conf: Allow bootin preferred provider to be overrideable

Since, meta-petalinux is a distro layer, config files here take
precedence over local.conf and any other config files. For microblaze
architecture, we can use xilinx-mcs recipe to generate bin/mcs files. We
need to allow PREFERRED_PROVIDER_virtual/boot-bin to be overrideable.

Signed-off-by: Bhargava Sreekantappa Gayathri <376fad44dca59011c5129585e3eb1fe4cc84fdaa@xilinx.com>
Signed-off-by: Manjukumar Matha <4c64a17569570cb9f1048973bce031c402b55312@xilinx.com>

Xilinx/meta-petalinux,Xilinx/meta-petalinux,Xilinx/meta-petalinux,Xilinx/meta-petalinux,Xilinx/meta-petalinux,Xilinx/meta-petalinux