Update LLVM/Clang snapshot to r192615, which defaults to libc++ and the
unwinder in libc on x86.
No David, '\?' is not the del character.  Broken in rev 1.21.
XXX pullup-5, pullup-6.
If the shell does not support the $LINENO variable, then use
"bfd_configure.lineno" instead of "configure.lineno" as the name of the
a version of the script that has had all uses of $LINENO converted to
literal line numbers.

Now building tools via "MKCROSSGDB=yes build.sh tools" works again, even
if the shell does not support $LINENO.

The previous problem was caused by an interaction
between the way .../gdb/dist/opcodes/configure executes
"${srcdir}/../bfd/configure --version", and the way both configure
scripts tried to create and then execute configure.lineno scripts.
Both configure.lineno scripts were created in the same OBJDIR,
with the configure.lineno from .../bfd/configure overwriting the
configure.lineno from .../opcodes/configure, while the latter was
still running.
Run ../bfd/configure under ${CONFIG_SHELL}, not under
the /bin/sh that happens to be mentioned in its "#!" line.
Small cleanup
Translate ENODEV to USBD_INVAL
Make this compile for more option combinations.
Switch to dwctwo(4) from dotg(4) for the RaspberryPi port.  This brings
DMA support and (initial) isoc transfer support.

Remove URTWN_DOTG_WORKAROUND as dwctwo doesn't appear to need it.
Clean up register read and write functions, add functions for 8-bit read and
write (needed to access config register). Add sysctl knob to set resolution
from user space.
Simplify sysctl handling.
Add information about user settable resolution via sysctl.
Adjust needed includes for fchmodat/mkdirat/mkfifoat/mknodat/fstatat
syscalls.
Update firmware from today 2013-10-15. Requested in PR/48288.
Instead of turning off the 8th bit on resume, turn it on, as it is on by
default. Problem reported by atatat@ when suspending vi and resuming loses
the ability to use the alt key.
Add sysctl knobs to set temperature limit and hysteresis. Reaching the limit
causes alert line of the chip to be asserted. These limits could be tied to
critical limit set in envsys, but it's more versatile to keep it as separate
value.
Add forgotten register definitions for previous commit.
Update man page to reflect latest changes (added sysctl knobs for temperature
limit and hysteresis).
s/with resolution/with a resolution/

Noticed by mbalmer@.
Basic man page for dwctwo.
Remove dotg(4) as it's been replaced by dwctwo(4).