Fix confusions related to encoding of instructions.

For __ARMEB__ in BE8 mode, instructions are encoded in little-endian.
Therefore, we need to swap bytes against these in native byte order.

In other cases, i.e., __ARMEL__ and __ARMEB__ in BE32 mode, instructions
are in native byte order, and we don't need to swap them.

Add breakpoint definitions for DTrace

branches: 1.8.44; 1.8.54; 1.8.60;
Remove arm support for IPKDB.

It hasn't worked since arm was broken out from arm32 in Jan 2001, and
no-one has noticed or cared to fix it.

branches: 1.7.46; 1.7.50; 1.7.52; 1.7.58; 1.7.66;
merge ktrace-lwp.

branches: 1.6.12;
Add a breakpoint instruction for Thumb.

branches: 1.5.2;
Use the GDB5 breakpoint value for the kernel breakpoint assembly statement
since this value will be properly recognized by gdb_trapper().
Pointed out by bsh. Thanks!

Add arm32 machine-specific remote kgdb support. Largely
from PR port-arm/15530 by bsh@, but with some updates from
me, including a fresh arm32/kgdb_machdep.c--ported from pc532.

branches: 1.3.4;
Recognize GDB's default breakpoint instruction (as of GDB 5.0), in addition to
the instruction we used with GDB 4.x. The new instruction has the advantage
of fitting the pattern that ARM recommend using for instructions that need to
stay undefined.

branches: 1.2.2; 1.2.6;
A bit of extra discussion based on the latest ARM ARM.

Header files which don't differ between arm32 and arm26 and can thus be
shared.