Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Convert to new FAST_DEPEND syntax for guessed dependencies.

This OBJS_DEPEND_GUESS is needed since each target gets its
own .depend.target.o file but also because it is spelled
.meta.target.o with WITH_META_MODE. The OBJS_DEPEND_GUESS
will apply the dependency if the required file is missing.

Also remove redundant .c files while here to avoid prolems with
targets using .ALLSRC and getting multiple source files.

Approved by: re (implicit)
Sponsored by: EMC / Isilon Storage Division

Update bmake glue to build GCC 4.2.

Also:
Switch FreeBSD to use libgcc_s.so.1.

Use dl_iterate_phdr to locate shared objects' exception frame
info instead of depending on older register_frame_info machinery.
This allows us to avoid depending on libgcc_s.so.1 in binaries
that do not use exception handling directly. As an additional
benefit it breaks circular libc <=> libgcc_s.so.1 dependency too.

Build newly added libgomp.so.1 library, the runtime support
bits for OpenMP.

Build LGPLed libssp library. Our libc provides our own
BSD-licensed SSP callbacks implementation, so this library
is only built to benefit applications that have hadcoded
knowledge of libssp.so and libssp_nonshared.a. When linked
in from command line, these libraries override libc
implementation.