MFC 289769,289822,290143,290144:
Rename remaining linux32 symbols from linux_* to linux32_*.

289769:
Rename remaining linux32 symbols such as linux_sysent[] and
linux_syscallnames[] from linux_* to linux32_* to avoid conflicts with
linux64.ko. While here, add support for linux64 binaries to systrace.
- Update NOPROTO entries in amd64/linux/syscalls.master to match the
main table to fix systrace build.
- Add a special case for union l_semun arguments to the systrace
generation.
- The systrace_linux32 module now only builds the systrace_linux32.ko.
module on amd64.
- Add a new systrace_linux module that builds on both i386 and amd64.
For i386 it builds the existing systrace_linux.ko. For amd64 it
builds a systrace_linux.ko for 64-bit binaries.

289822:
Fix build for the KTR-enabled kernels.

290143:
Fix build with DEBUG defined.

290144:
Update for LINUX32 rename. The assembler didn't complain about undefined
symbols but just used 0 after the rename.

MFC r257037: Redefine the io provider using the SDT(9) macros

MFC slacker: markj

MFC r256543,r259245,r259421,r259668,r259674

r256543:

Add fasttrap for PowerPC. This is the last piece of the DTrace/ppc puzzle.
It's incomplete, it doesn't contain full instruction emulation, but it should be
sufficient for most cases.

r259245,r259421: (FBT)

FBT now does work fully on PowerPC.

Save r3 before using it for the trap check, else we end up saving the new r3,
containing the trap instruction encoding (0x7c810808), and restoring it back
with the frame on return. This caused it to panic on my ppc32 machine.

r259668,r259674:
Fix a typo in the FBT code.

MFC r257037: Redefine the io provider using the SDT(9) macros

MFC slacker: markj

MFC r256543,r259245,r259421,r259668,r259674

r256543:

Add fasttrap for PowerPC. This is the last piece of the DTrace/ppc puzzle.
It's incomplete, it doesn't contain full instruction emulation, but it should be
sufficient for most cases.

r259245,r259421: (FBT)

FBT now does work fully on PowerPC.

Save r3 before using it for the trap check, else we end up saving the new r3,
containing the trap instruction encoding (0x7c810808), and restoring it back
with the frame on return. This caused it to panic on my ppc32 machine.

r259668,r259674:
Fix a typo in the FBT code.