darwin: Cleanup and fixes related to Mac OS IOUSBLib interface checks

darwin: Cleanup and fixes related to Mac OS IOUSBLib interface checks

- revisited fix to issue #48:
  - guard kIOUSBDeviceInterfaceID500 with 10.8 deployment (not 10.9).
    I believe a typo in the bug report caused this to be guarded too
    strictly.
  - added deployment target tests to every interface check. Necessary
    because merely checking for a macro definition tells us nothing
    about what features are available at runtime. It is common to build
    against new SDKs but deploy to older OSes.
- properly guard kIOUSBInterfaceInterfaceID700 against 10.10 deployment
  (not 10.9).  It was added in 10.10.  Probably a copy-pasto.
- changed non-existent kIOUSBDeviceInterfaceID220 to
  kIOUSBDeviceInterfaceID197.  Probably a copy-pasto.
- don't use defines like MAC_OS_X_VERSION_10_9 since they don't exist in
  older SDKs and would fail to compile, use raw numbers instead.
- added tests for newer interfaces: kIOUSBInterfaceInterfaceID800,
  kIOUSBInterfaceInterfaceID650, kIOUSBDeviceInterfaceID650.

Signed-off-by: Chris Dickens <christopher.a.dickens@gmail.com>