This makes three changes to the patches for 10.4 and 10.5:

1) In the G3 patch, it removes the ppc7400 reference that was never
actually used, rather than updating it.  It still fixes the case that
is actually used.

2) It removes the patch for i386 assembler that has been
(approximately) incorporated upstream since v3.4.5.  The collision
with this patch was the reason for the patch failure.

3) For the gcc 4.2 test-build fix, it replaces the conditionally
applied patchfile with an unconditional patch controlled by an
environment variable, thereby keeping the source code consistent
across OS versions.  This new environment variable is now defined by
the Portfile when the compiler is gcc 4.2.

The patches for #1 and #3 are now in a single unified patchfile.

Closes: https://trac.macports.org/ticket/69380

TESTED:
Tested on 10.4-10.5 ppc, 10.5-10.6 ppc (x86_64 Rosetta), 10.4-10.6
i386, 10.4-12.x x86_64, and 11.x-14.x arm64.
Now builds and passes at least some tests on all tested platforms,
except 10.4 ppc +universal.
Test behavior on 10.6+ is essentially unchanged.  Tests on 10.4 and
10.5 have a few additional failures since v3.4.4 (the last version
that built successfully) due to new tests having been added.

This makes a number of changes to the Portfile:

1) Removes the superfluous dependency on expect.  This was probably a
holdover from a time when dejagnu was missing the expect dependency.
Not only is this dependency superfluous (since the tests don't
reference expect directly), but it's also more heavy-handed since
dejagnu's expect dependency only applies when the OS-supplied expect
is too old.

2) Fixes the build to get the default architecture correctly.  This is
a general fix that replaces the narrow fix for the 10.6/ppc/Rosetta
case.  See the Portfile comments for details.

3) Removes the tweak to force the use of the integrated assembler when
building with clang.  This is now obsolete (since all builds work
without it), and causes some slightly inferior results in some tests.

4) Made the clearing of cxx_stdlib unconditional.  This was only
being done in the specific case where not doing so led to a circular
dependency, but since libffi doesn't use C++ at all, it's preferable
to do it in all cases and avoid unnecessary compiler constraints.
See the Portfile comments for more details.

5) Adds myself as the maintainer (previously nomaintainer).

Since #3 may affect the installed content in some cases, it includes a
revbump.  No revbumping of dependents is necessary.

TESTED:
Tested on 10.4-10.5 ppc, 10.5-10.6 ppc (x86_64 Rosetta), 10.4-10.6
i386, 10.4-12.x x86_64, and 11.x-14.x arm64.
Builds on all tested platforms except 10.5 ppc +universal, with
test results equal to or better than the previous state.