efi_loader: rename BOOTEFI_BOOTMGR to EFI_BOOTMGR

At this point, EFI boot manager interfaces is fully independent from
bootefi command. So just rename the configuration parameter.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/boot/Makefile b/boot/Makefile
index a47e002..f0a279c 100644
--- a/boot/Makefile
+++ b/boot/Makefile
@@ -35,7 +35,7 @@
 obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_SCRIPT) += bootmeth_script.o
 obj-$(CONFIG_$(SPL_TPL_)CEDIT) += cedit.o
 ifdef CONFIG_$(SPL_TPL_)BOOTSTD_FULL
-obj-$(CONFIG_BOOTEFI_BOOTMGR) += bootmeth_efi_mgr.o
+obj-$(CONFIG_EFI_BOOTMGR) += bootmeth_efi_mgr.o
 obj-$(CONFIG_$(SPL_TPL_)EXPO) += bootflow_menu.o
 obj-$(CONFIG_$(SPL_TPL_)BOOTSTD) += bootflow_menu.o
 endif