d2lte: add d2tfnspr and d2spi

d2spi does not need a separate section in props because the bootloader
string, SCH-L710, matches what we look for for d2spr, SPH-L710

Conflicts:
	BoardConfig.mk

Change-Id: If9bb4098b1e4538a1fdc05c16a6357b2c8f58542