selftests/timens: timerfd: Use correct clockid type in tclock_gettime()

tclock_gettime() is a wrapper around clock_gettime().
The first parameter of clock_gettime() is of type "clockid_t",
not "clock_t".

Use the correct type instead.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Thomas Weißschuh <[e-mail]>
Reviewed-by: Muhammad Usama Anjum <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

tools/testing/selftests/timens/timerfd.c

···
 #include "log.h"
 #include "timens.h"
 
-static int tclock_gettime(clock_t clockid, struct timespec *now)
+static int tclock_gettime(clockid_t clockid, struct timespec *now)
 {
 	if (clockid == CLOCK_BOOTTIME_ALARM)
 		clockid = CLOCK_BOOTTIME;