tunables: don't assert initialisation in impl getters

It actually doesn't matter if it's not initialised when we first query
the current value; it just returns empty-string. A crash is quite
obnoxious even if it is a rare case.

Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Pavel Snajdr <snajpa@snajpa.net>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #17377

module/zfs/vdev_raidz_math.c

@@ -643,8 +643,6 @@ vdev_raidz_impl_get(char *buffer, size_t size)
 	char *fmt;
 	const uint32_t impl = RAIDZ_IMPL_READ(zfs_vdev_raidz_impl);
 
-	ASSERT(raidz_math_initialized);
-
 	/* list mandatory options */
 	for (i = 0; i < ARRAY_SIZE(math_impl_opts) - 2; i++) {
 		fmt = (impl == math_impl_opts[i].sel) ? "[%s] " : "%s ";