[gdb/testsuite] Clean up formatting in gdb/contrib/cc-with-tweaks.sh

In emacs, on gdb/contrib/cc-with-tweaks.sh, do:
- M-x whitespace-cleanup,
- M-x mark-whole-buffer and M-x indent-region, and
- and undo the unwanted changes in the header comment.

Only whitespace changes.

Tested on x86_64-linux.

Approved-by: Kevin Buettner <kevinb@redhat.com>