fix '/include/openbsc ' to have no trailing space

The newline and $NULL manage to append a trailing space to the 'openbsc' dir.

This was broken in commit 7b6673fa06dada3ec4586b1c0d735e9df4177a48
"Consistenly format variables in */Makefile.am files"
by Change-Id Ifa21513c007072314097b7bec188579972dc1694

Add a comment to prevent this in the future.

Reported-by: Andreas Mueller <andreas.mueller@criticallabs.org>
Change-Id: I218027459e3b2aaa817d91eb3f69d9c0b10dcd4e
1 file changed
tree: 4c5a0db14945c104ddc8f4c25a3df759528b39be
  1. contrib/
  2. debian/
  3. openbsc/
  4. .gitignore
  5. .gitreview
  6. .mailmap