uboot-imx

test: dm: core: Add a test case for driver marked with DM_FLAG_PRE_RELOC flag

Now that we fixed the pre-relocation driver binding for driver marked
with DM_FLAG_PRE_RELOC flag, add a test case to cover that scenario.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>