Fix various typos

Correct an assortment of typos throughout the code base.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #11774

lib/libzfs/libzfs_dataset.c

@@ -5334,7 +5334,7 @@ zfs_get_holds(zfs_handle_t *zhp, nvlist_t **nvl)
  * 160k.  Again, 128k is from SPA_OLD_MAXBLOCKSIZE and 160k is as calculated in
  * the 128k block example above.
  *
- * The situtation is slightly different for dRAID since the minimum allocation
+ * The situation is slightly different for dRAID since the minimum allocation
  * size is the full group width.  The same 8K block above would be written as
  * follows in a dRAID group:
  *

lib/libzfsbootenv/lzbe_device.c

@@ -83,7 +83,7 @@ lzbe_set_boot_device(const char *pool, lzbe_flags_t flag, const char *device)
 	} else {
 		/*
 		 * Use device name directly if it does start with
-		 * prefix "zfs:". Otherwise, add prefix and sufix.
+		 * prefix "zfs:". Otherwise, add prefix and suffix.
 		 */
 		if (strncmp(device, "zfs:", 4) == 0) {
 			fnvlist_add_string(nv, OS_BOOTONCE, device);

lib/libzutil/zutil_import.c

@@ -1408,7 +1408,7 @@ discover_cached_paths(libpc_handle_t *hdl, nvlist_t *nv,
 
 	/*
 	 * Once we have the path, we need to add the directory to
-	 * our directoy cache.
+	 * our directory cache.
 	 */
 	if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) == 0) {
 		return (zpool_find_import_scan_dir(hdl, lock, cache,