vtime: Convert vtime_seqlock into raw_spinlock_t and seqcount combo

The vtime seqlock needs to be taken in true interrupt context on -rt.
The normal seqlocks are converted to mutexes when PREEMPT_RT_FULL is
enabled, which will break the vtime code as the calls are done from
interrupt context.

Convert the vtime seqlock into the raw_spinlock_t and seqcount combo
that can be done in interrupt context.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

4 files changed