lttng: Prevent creation of incorrect .o files when generating from .tp

Signed-off-by: Adam Crume <adamcrume@gmail.com>
lttng: Prevent deletion of tracing-common.h when cleaning

Signed-off-by: Adam Crume <adamcrume@gmail.com>
lttng: Split up libtracepoints

Signed-off-by: Adam Crume <adamcrume@gmail.com>