cris: correct syscall numbers in unistd.h for timerfd_settime and timerfd_gettime

Last commit for unistd was not correct, it only had a partial update of
syscall numbers for __NR_timerfd_settime and __NR_timerfd_gettime.  Also,
NR_syscalls was not incremented for the new syscalls.

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>