vbe: Add initial support for VBE

Create a new bootmeth for VBE along with a library to handle finding the
VBE methods.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/boot/Makefile b/boot/Makefile
index 854b391..c52c969 100644
--- a/boot/Makefile
+++ b/boot/Makefile
@@ -46,3 +46,5 @@
 ifdef CONFIG_SPL_BUILD
 obj-$(CONFIG_SPL_LOAD_FIT) += common_fit.o
 endif
+
+obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_VBE) += vbe.o