Revert "test_firmware: Test platform fw loading on non-EFI systems"

This reverts commit 18efb2f9

 as it is
reported to break the build:
	https://lore.kernel.org/r/20200909154709.619fe9bb@canb.auug.org.au

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 18efb2f9

 ("test_firmware: Test platform fw loading on non-EFI systems")
Cc: stable@vger.kernel.org
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Scott Branden <scott.branden@broadcom.com>
Cc: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200909154709.619fe9bb@canb.auug.org.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>