of/flattree: make of_fdt.h safe to unconditionally include.
of/flattree: make of_fdt.h safe to unconditionally include.

If CONFIG_OF_FLATTREE is not set, then don't process the body of
linux/of_fdt.h

Signed-off-by: Grant Likely <9069e6f5a2b566e2674a0ba1e2bf39c12c195fad@secretlab.ca>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas