Makefile.inc: Rewrite $(files-in-dir)

The `files-in-dir` macro is supposed to return all files (out of a
given set) that reside directly (non-recursive) in a given directory.
While the current solution worked splendidly, we can achieve the same
without recursive macros that look at each parent dir individually.

Beside providing better readability, this also fixes a future make
error, as make doesn't like the variable name ` ` anymore ;)

Change-Id: Iac0eacdf91b8b5098592ad301c1f3fdb632454e9
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/27324
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
1 file changed