trace-cmd: Add new local function to check if a trace clock is supported

A new local function is added to check if a given trace clock is
supported by the ftrace:
 clock_is_supported()
And test that the passed in clock is supported.
The logic should be part of the tracefs library, when a tracefs API is
implemeneted, this local funciton will be removed.

Link: https://lore.kernel.org/linux-trace-devel/20210325064055.539554-6-tz.stoyanov@gmail.com

Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
[ Added test to make sure passed in clock is supported ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
1 file changed