sched_ext: Fix spelling mistake: "intead" -> "instead"

There is a spelling mistake in the help text. Fix it.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

tools/sched_ext/scx_qmap.c

@@ -31,7 +31,7 @@ const char help_fmt[] =
 "  -d PID        Disallow a process from switching into SCHED_EXT (-1 for self)\n"
 "  -D LEN        Set scx_exit_info.dump buffer length\n"
 "  -S            Suppress qmap-specific debug dump\n"
-"  -p            Switch only tasks on SCHED_EXT policy intead of all\n"
+"  -p            Switch only tasks on SCHED_EXT policy instead of all\n"
 "  -v            Print libbpf debug messages\n"
 "  -h            Display this help and exit\n";