native: lib: Remove obsolete 'struct timezone' usage.

The use of the 'struct timezone' data type is prohibited. It is
legacy and should not be used.

Signed-off-by: Steven J. Hill <sjhill@realitydiluted.com>
native: Link in threads library for test applications.

Various tests require the usage of the pthreads library when
using the V4 interface.

Signed-off-by: Steven J. Hill <sjhill@realitydiluted.com>
native: Use new context structure for V4 interface.

Changes to the native library to use '_gckCONTEXT' instead of
'_gcoCONTEXT' when compiled for the V4 interface. These changes
allow the 'reset' and 'viv_info' applications to build. The
'viv_info' test application works and 'reset' does not.

Signed-off-by: Steven J. Hill <sjhill@realitydiluted.com>