libtraceevent: Remove global input buffer

When using the library with multiple threads, the global input buffer
pointer gets modified concurrently by each thread. An easy fix for the
problems that arise is to give each struct tep_handle its own input
buffer pointer.

Link: https://lore.kernel.org/linux-trace-devel/20221216102754.257174-1-balbi@kernel.org

Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
3 files changed