Protocol bump from 9 to 10

Protocol bump from 9 to 10

Bump LTTNG_UST_ABI_MAJOR_VERSION from 9 to 10, but keep backward
compatibility unchanged (oldest compatible 8) for applications linked
against older liblttng-ust.

With this protocol bump, we can send a 64-bit "id" in the event
registration reply. We keep the 32-bit event id field for now, until we
can proceed to bump the oldest compatible major number.

The 64-bit id field is useful for events within "counter" channels, but
there is no point in keeping a 32-bit value solely for the ring buffer
channel.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ibd3da4c8156886a6d2f6555462526bb717c451dd