Makefile: Run defconfig files through the C preprocessor

This allows us to use some of the normal preprocessor directives inside
defconfig files. Such as #define and #include.

Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Nishanth Menon <nm@ti.com>
1 file changed