Pass also Xcode's ARCHS, OTHER_CFLAGS and OTHER_CPLUSPLUSFLAGS in lo.xcconfig

ARCHS tells Xcode to build the architecture for which the LO code has
been built. The CFLAGS properties make sure the same -D flags are used
as for the LO code.

Change-Id: I3c8af0ff9fba7d0b4eddbc0af9aad44fb385314c