make: add provision to get CFLAGS for LE

For Rocko, gcc version is upgraded to 6.4, which adds new flags by default
which are causing issues in LK. Inorder to pass the dependent CFLAGS
LKLE_CFLAGS variable is added which appends all flags passed by yocto.

Change-Id: I171a8d1c8f18069fd6bb19ccbf5ad221a8b99f5d
1 file changed