Log Message:
Update to libFirm 1.21.0
This lets the package build on NetBSD/i386.

libFirm 1.21.0 (2012-11-16)
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* Improvements of x86 backend (esp. x87 floatingpoint code)
* Improvements to sparc backend (better use of delay slots)
* Improved local optimisation rules (esp. conversions)
* Make compiler more deterministic
* Bugfixes

libFirm 1.20.0 (2011-12-07)
---------------------------

* Further improvemens to sparc backend (SPEC2000 works with softfloat)
* Tuning of x86 backend
* Software floatingpoint lowerer
* Fixed firm profiling
* New pass management allowing to specify pre-/postconditions for passes
* Remove dependency on liblpp, add support for gurobi ILP solver
* Experimental dwarf debugging support
* Code cleanups, refactoring
* Restructured API documentation
* Bugfixes (we did alot of csmith testing)

libFirm 1.19.1 (2011-05-17)
---------------------------

* Fix some set_XXX functions not being exported in the shared library

libFirm 1.19.0 (2011-03-15)
---------------------------

* Includes "SSA-Based Register Allocation with PBQP"
* Improved Sparc backend
* New (optimistic) fixpoint based value-range propagation/bit analysis
* Code cleanup and refactoring
* Bugfixes

libFirm 1.18.1 (2010-05-05)
---------------------------

* Fix bug where stackframe was not always setup for -fno-omit-frame-pointer
* bugfixes in Asm handling

libFirm 1.18.0 (2010-04-15)
---------------------------

* Includes "Preference Guided Register Assignment" algorithm
* Experimental Value Range Propagation
* Loop Inversion and experimental Loop Unrolling code
* Simplified construction interface. Most node constructors don't need \ 
graph/block arguments anymore.
* Reworked type interface. Type names are optional now. Support for additional \ 
linkage types that among others support C++ 'linkonce' semantics now.
* Small changes in constructors and node getters/setters (mostly adding 'const' \ 
to some getters)
* code cleanup, smaller improvements in API specification
* bugfixes