efi_loader: Allow to compile helloworld.efi w/o bundling it

Today we can compile a self-contained hello world efi test binary that
allows us to quickly verify whether the EFI loader framwork works.

We can use that binary outside of the self-contained test case though,
by providing it to a to-be-tested system via tftp.

This patch separates compilation of the helloworld.efi file from
including it in the u-boot binary for "bootefi hello". It also modifies
the efi_loader test case to enable travis to pick up the compiled file.
Because we're now no longer bloating the resulting u-boot binary, we
can enable compilation always, giving us good travis test coverage.

Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Tom Rini <trini@konsulko.com>

lib/efi_loader/Makefile

@@ -10,6 +10,9 @@
 CFLAGS_helloworld.o := $(CFLAGS_EFI)
 CFLAGS_REMOVE_helloworld.o := $(CFLAGS_NON_EFI)
 
+efiprogs-$(CONFIG_CMD_BOOTEFI_HELLO_COMPILE) += helloworld.efi
+always := $(efiprogs-y)
+
 obj-$(CONFIG_CMD_BOOTEFI_HELLO) += helloworld_efi.o
 obj-y += efi_image_loader.o efi_boottime.o efi_runtime.o efi_console.o
 obj-y += efi_memory.o