GLES_trace: fix compile errors on 64 bit architectures

GLES_trace passes some pointers back to the host. Encode them
using int64's rather than int32's

This fix requires an update to the host tool to look at pointers
as 64 bit, and if not found, then fall back to 32 bit integers.

Change-Id: I11ff2ca51290f05913c1b9143cecee1caf015543