Various fixes to the tree to get coreboot-v2 to build on Solaris

Various fixes to the tree to get coreboot-v2 to build on Solaris

- Replace $(PWD) with $(CURDIR) in Makefiles. I don't know why
  the Solaris version behaves differently, but CURDIR is a safe
  choice on gnu make (and we require gnu make already)
- Use tail -1 instead of tail -n1 in a file that already relies on
  tail -1 support in another place
- Use tail -1 as alternative to tail -n1 in another place
- Use #define for ulong_t in romcc, as that name is used on Solaris
- Avoid fprinting a null pointer. The standard doesn't mandate that
  this is a special case, and Solaris doesn't implement it that way.

Signed-off-by: Patrick Georgi <patrick.georgi@coresystems.de>
Acked-by: Ronald G. Minnich <rminnich@gmail.com>
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@4305 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1