cmd: load: add load command for memory mapped

cp.b is used a lot as a way to load binaries to memory and execute
them, however we may need to integrate this with the efi subsystem to
set it up as a bootdev.

So, introduce a loadm command that will be consistent with the other
loadX commands and will call the efi API's.

ex: loadm $kernel_addr $kernel_addr_r $kernel_size

with this a kernel with CONFIG_EFI_STUB enabled will be loaded and
then subsequently booted with bootefi command.

Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/test/cmd/Makefile b/test/cmd/Makefile
index a59adb1..4b2d7df 100644
--- a/test/cmd/Makefile
+++ b/test/cmd/Makefile
@@ -7,6 +7,7 @@
 endif
 obj-y += mem.o
 obj-$(CONFIG_CMD_ADDRMAP) += addrmap.o
+obj-$(CONFIG_CMD_LOADM) += loadm.o
 obj-$(CONFIG_CMD_MEM_SEARCH) += mem_search.o
 obj-$(CONFIG_CMD_PINMUX) += pinmux.o
 obj-$(CONFIG_CMD_PWM) += pwm.o