build system: change addition order of files to go by region

Instead of adding each file in all requested regions, sort by region,
then by file.

This is in preparation of per-region file options
(eg. position, alignment)

Change-Id: Ide09a1c8840279380294a059bbd5d2f9f0cba780
Signed-off-by: Patrick Georgi <>
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <>
Reviewed-by: Martin Roth <>
1 file changed