cmd/Makefile has:
ifdef CONFIG_FPGA
obj-$(CONFIG_CMD_FPGA) += fpga.o
endif
which means that if CONFIG_FPGA is not set, CONFIG_CMD_FPGA silently
does nothing. Let's remove that Makefile conditional and instead express
this equivalent dependency in Kconfig, so a lot of redundant
# CONFIG_CMD_FPGA is not set
can be removed from board defconfigs that don't actually have an FPGA.
Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com>