libcpp: Merge fixes from upstream

GCC preprocessor/29966:
* macro.c (lex_expansion_token): Save and restore cpp_reader's
cur_token.
(_cpp_create_definition): Don't restore cur_token here.
* lex.c (_cpp_lex_token): Added assertion.

GCC preprocessor/28709:
* macro.c (paste_tokens): Remove PASTE_LEFT from the old lhs.

GCC c/31924
* expr.c (interpret_float_suffix): Check for invalid suffix.

GCC preprocessor/14331
* lex.c (_cpp_get_fresh_line):  Don't warn if no newline at EOF.

Fixup whitespacing

Obtained from:	gcc per-4.3 (rev. 121340, 124356, 124358, 124730,
				  125212, 125255 ; GPLv2)
MFC after:	3 weeks
Log the rx ring offset as part of the debug message.
Add a nand flash controller driver for Atmel at91 family.  Tested only
on at91rm9200 so far.

The files.at91 has listed a nand driver for ages, but it never existed.
Overhaul the iwn(4) scan infrastructure to be slightly more "correct"
for these chipsets.

* Correctly set the active/passive flag in the scan request - this is
  NOT a "is the channel active|passive"; it's to do with whether we
  have an SSID to actively scan for or not.  The firmware takes care
  of the active/passive setup of the channel.

* Calculate the active/passive dwell time based on the beacon interval
  and the channel mode, rather than using a hard coded value.

* For now, hardcode the scan service_time.  It's defined as:

  31:22 - number of beacon intervals to come back onto the home channel
          for;
  0:21  - time (microseconds) to come back onto the home channel for.

  When doing an active scan when the NIC is active (whether we're associated
  or not - it only matters if we've setup the NIC to a destination or not)
  this determines how much time to stay on the home channel for when
  scanning.  We can tune this based on the amount of active traffic.

  For now it's 4 beacon intervals and 100 microseconds.

* Fix the "good crc threshold" setting.  It differs based on the NIC
  firmware.  Some older firmware required a workaround; the later
  firmware instead treats the field as a flag.

* Enforce that we are not sending a scan command if one is already
  pending.  Any time this is done is a bug and it absolutely needs
  to be fixed - so be very loud.

* Add the SCAN flag to a few debug messages that are scan related but
  only occuring under STATE.

Now, this does get noisy when you're scanning in an actively busy 2GHz
network as the firmware (for reason I don't quite yet understand) seems
hell bent on staying on some passive channels longer than it should.
However, it should eventually recover and complete the scan.

This is a work in progress; please let me know if things get stuck or
if things improve!

Tested:

* intel centrino 2200
* intel centrino 2230
* intel 6200
* intel 5100
* intel 4965 (gets upset, but that's a known issue)

Obtained from:	linux iwlwifi