loccal.conf.sample: Update to use latest XSDK
loccal.conf.sample: Update to use latest XSDK

Use GCCv6.2 for MB

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