Fix Freelook on Linux and add speed reset.

Should fix issue 7692.
Also fixes issue 7147.

I have no idea if these changes will affect Mac or Windows users, so please test.
Update freelook description.
Updated GCM references to ISO
VideoConfigDiag: Updated video resolution description

Changed description to recommend selecting "auto"
JIT: micro-optimize cmpXX a bit more for lower latency/code size
JIT: use BLR optimization to avoid anding LR with 0xFFFFFFFC

Should save roughly one instruction per blr.
JIT: reorder blr comparisons

This should allow macro-op fusion in blr instructions.
JIT: optimize mulhwu
JIT: merge fcmpx and cror

Almost all uses of boolean condition-register ops in real code seem to be
the combination fcmpx + cror (e.g. for <= or >=). This merges the two.
JIT: optimize crclr special case of crxor
JIT: flush unused registers during branch merges

Also correct some flags in interpreter tables.
ConfigMain: Added missing filetypes to default ISO options
Reorganize faulting stuff.  Differentiate between arch- and OS-specific defines.

- Get rid of ArmMemTools.cpp and rename x64MemTools.cpp to MemTools.cpp.
  ArmMemTools was almost identical to the POSIX part of x64MemTools, and
  the two differences, (a) lack of sigaltstack, which I added to the
  latter recently, and (b) use of r10 to determine the fault address
  instead of info->si_addr (meaning it only works for specifically
  formatted JIT code), I don't think are necessary.  (Plus Android, see
  below.)

- Rename Core/PowerPC/JitCommon/JitBackpatch.h to Core/MachineContext.h.
  It doesn't contain anything JIT-specific anymore, and e.g. locking
  will want to use faulting support regardless of whether any JIT is in
  use.

- Get rid of different definitions of SContext for different
  architectures under __linux__, since this is POSIX.  The exception is
  of course Android being shitty; I moved the workaround definition from
  ArmMemTools.cpp to here.

- Get rid of #ifdefs around EMM::InstallExceptionHandler and just
  provide an empty implementation for unsupported systems (i.e.
  _M_GENERIC really).  Added const bool g_exception_handlers_supported
  for future use; currently exception handlers are only used by the JIT,
  whose use implies non-M_GENERIC, but locking will change that.

- Remove an unnecessary typedef.
VideoCommon: Remove GetPointer in fifo code
Merge pull request #1401 from Stevoisiak/updateResolutionTooltip

VideoConfigDiag: Updated video resolution description
Move GLInterface to the OGL VideoBackend's directory.
Updated android GCM references to ISO
Merge pull request #1398 from Stevoisiak/setDefaultISOFiletypes

ConfigMain: Added missing filetypes to default ISO options
Merge pull request #1264 from Stevoisiak/GCM-to-ISO

Gcm to iso
DolphinQt: adapt so that it can boot games.